If f(x) = 3x + 7, find f(a - 1)

Answers

Answer 1

Answer:

3a+4

Step-by-step explanation:

f(x) = 3x + 7,

Let x = a-1

f(a - 1) = 3(a-1) +7

           Distribute

            =3a -3 +7

            = 3a +4


Related Questions

Simplify the expression below.
14a8y3 - 7 Ay5 + 28a12y2
7aty
A.
OB.
2a²y3 - ay5 + 4a3y2
2a4y? - JA + 428 y
2a4y3 – 5 + 428 y?
D. 2012,4 - 2876 +4215,3
C.

Answers

Answer:

14a8y3 - 7 Ay5 + 28a12y2-  7ay2 • (4a11 + 2a7y - y3)

Step-by-step explanation:

Equation at the end of step  1  :

 (((14•(a8))•(y3))-(7a•(y5)))+((22•7a12)•y2)

Step  2  :

Equation at the end of step  2  :

 (((14•(a8))•(y3))-7ay5)+(22•7a12y2)

Step  3  :

Equation at the end of step  3  :

 (((2•7a8) • y3) -  7ay5) +  (22•7a12y2)

Pull out like factors

Answer:   7ay2 • (4a11 + 2a7y - y3)

Hope this helps.

Suppose the round-trip airfare between Philadelphia and Los Angeles a month before the departure date follows the normal probability distribution with a mean of $387.20 and a standard deviation of $68.50. What is the probability that a randomly selected airfare between these two cities will be between $325 and $425?

Answers

Answer:

52.74% probability that a randomly selected airfare between these two cities will be between $325 and $425

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this question, we have that:

[tex]\mu = 387.20, \sigma = 68.50[/tex]

What is the probability that a randomly selected airfare between these two cities will be between $325 and $425?

This is the pvalue of Z when X = 425 subtracted by the pvalue of Z when X = 325. So

X = 425

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{425 - 387.20}{68.50}[/tex]

[tex]Z = 0.55[/tex]

[tex]Z = 0.55[/tex] has a pvalue of 0.7088

X = 325

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{325 - 387.20}{68.50}[/tex]

[tex]Z = -0.91[/tex]

[tex]Z = -0.91[/tex] has a pvalue of 0.1814

0.7088 - 0.1814 = 0.5274

52.74% probability that a randomly selected airfare between these two cities will be between $325 and $425

Josh is a product designer for electrical company he designed a new table lamp Josh will use plastic to make the lamp he uses this formula to work out the amount of plastic needed P= b2 +2bh.the lenght of the base of the lamo will be 13cm the slope of the lamp will be 34cm.josh thinks the amount of plastic needed will be less than 1000cm2​

Answers

Answer:

Josh is right, he needs less than 1000 square centimeters.

Step-by-step explanation:

We can find the height using Pythagorean's Theorem.

[tex]34^{2} =13^{2} +h^{2} \\h=\sqrt{1,156-169}=\sqrt{987} \approx 31[/tex]

So, the height is 31 centimeters, approximately.

Now, we use the given expression and the base and height

[tex]P=b^{2} +2bh=13^{2}+2(13)(31)=169+806=975 \ cm^{2}[/tex]

Therefore, Josh is right, he needs less than 1000 square centimeters. Specifically, he needs 975 square centimeters.


Please help

The lengths of pregnancy terms for a particular species of mammal are nearly normally distributed about a mean pregnancy length with a standard deviation of 17 days. About what percentage of births would be expected to occur within 51 days of the mean pregnancy​ length?

Answers

Answer:

About 99.7% of births would be expected to occur within 51 days of the mean pregnancy​ length

Step-by-step explanation:

The Empirical Rule states that, for a normally distributed random variable:

68% of the measures are within 1 standard deviation of the mean.

95% of the measures are within 2 standard deviation of the mean.

99.7% of the measures are within 3 standard deviations of the mean.

In this problem, we have that:

Standard deviation = 17.

About what percentage of births would be expected to occur within 51 days of the mean pregnancy​ length?

51/17 = 3.

So, within 3 standard deviations of the mean.

About 99.7% of births would be expected to occur within 51 days of the mean pregnancy​ length

Each big square below represents one hole what percent is represented by the shaded area

Answers

Answer:

  145%

Step-by-step explanation:

There are 100 small squares in each large square. Since 100% is one whole, each small square represents 1%.

Count the shaded small squares. The process is made easier by the fact that there are 10 in a row.

145 small squares are shaded, so the percentage represented is ...

  145%

The function fff is given in three equivalent forms. Which form most quickly reveals the zeros (or "roots") of the function? Choose 1 answer: Choose 1 answer: (Choice A) A f(x)=-3(x-2)^2+27f(x)=−3(x−2) 2 +27f, (, x, ), equals, minus, 3, (, x, minus, 2, ), squared, plus, 27 (Choice B) B f(x)=-3(x+1)(x-5)f(x)=−3(x+1)(x−5)f, (, x, ), equals, minus, 3, (, x, plus, 1, ), (, x, minus, 5, )(Choice C) C f(x)=-3x^2+12x+15f(x)=−3x 2 +12x+15f, (, x, ), equals, minus, 3, x, squared, plus, 12, x, plus, 15 Write one of the zeros. xxx =

Answers

Answer:

(B) [tex]f(x)=-3(x+1)(x-5)[/tex]

x=5

Step-by-step explanation:

Given the three equivalent forms of f(x):

[tex]f(x)=-3(x-2)^2+27\\f(x)=-3(x+1)(x-5)\\f(x)=-3x^2+12x+15[/tex]

The form which most quickly reveals the zeros (or "roots") of f(x) is

(B) [tex]f(x)=-3(x+1)(x-5)[/tex]

This is as a result of the fact that on equating to zero, the roots becomes immediately  evident.

[tex]f(x)=-3(x+1)(x-5)=0\\-3\neq 0\\Therefore:\\x+1=0$ or x-5=0\\The zeros are x=-1 or x=5[/tex]

Therefore, one of the zeros, x=5

Answer:

i dont think the one above is correct. here is the correct answer

Step-by-step explanation:

the table shows jills math quiz scores. what is the minimum score she needs on her next quiz to have a mean of at least 92
week 1: 92
week 2: 96
week 3: 94
week 4: 88

Answers

Answer:90

Step-by-step explanation:

The minimum score she needs on her next quiz is 90

What is mean ?

The mean is the average value which can be calculated by dividing the sum of observations by the number of observations

The mean value of the data set is the ratio of sum of data set's values to number of values it has.

If the data set consists of values

Mean = Sum of observations/the number of observations

[tex]\overline{x} = \dfrac{x_1 + x_2 + \cdots + x_n}{n}[/tex]

Given;

Mean of 5 weeks= 92

Mean= (week 1 + week 2 + week 3 + week 4+ week 5)/number of weeks

         let, the score of next week be x

                  Mean = (92+96+94+88+x)/5

      putting the value of mean;

                     92= (370+x)/5        

                      460=370+x

                       x=460-370

                        x=90

In the next quiz jills need 90 score to get the mean of 92.

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During one year Saul takes 15 credit hours for each three quarters. Tuition and fees amount to $608 per credit hour. Textbooks average $420 per quarter. The prorated monthly cost for tuition and fees and textbooks is?

Answers

Answer:

Total textbook cost of tuition fees per month will be $ 2,356 and 25 cents

Step-by-step explanation:

To solve the exercise, we will first define the total cost per quarter.

cost of 1 credit hour = $ 601

then we solve the following:

cost of 15 credit hours = $ 601 * 15 = $ 9015

textbooks = $ 410

then we solve the following:

total cost = 9015 + 410 = $ 9425

total cost for 3 quarters = 3 * $ 9425 = $ 28275 for 12 months

we calculate as follows

Total textbook cost of tuition fees per month will be

$ 28,275 / 12 = $ 2,356 and 25 cents

25 POINTS HELP ASAP , Please read question THEN answer correctly also will give BRAINLIEST! No guessing.

Answers

Answer:

B and D

Step-by-step explanation:

Simply set each factor, that is the expression in each set of brackets equal to 0;

This will give the equations that you need to solve to get the roots.

Which value has an absolute deviation of 5 from the mean of this data set?
26, 12, 35, 28, 14
A 28
B. 35
C. 26
D. 14

Answers

Answer: 28

Step-by-step explanation: see prev. explanation

The absolute deviation of 5 from the mean of this data set is 28.

What is absolute deviation?

Absolute deviation is "the distance between each data point to the mean".

According to the question,

The data set is 26, 12, 35, 28, 14

Average of the data set = [tex]\frac{sum of the data value }{Total number of observation}[/tex]

= [tex]\frac{26+12+35+28+14}{5}[/tex]

= [tex]\frac{115}{5}[/tex]

= 23.

Thus, the average of the data set is 23.

In order to find absolute deviation of 5 subtract each data point from the mean.

26 - 23 = |3| = 3

12 - 23  = |-11| = 11

35 - 23 = |12| = 12

28 - 23 = |5| =  5

14 - 23  = |-9| = 9.

Hence, the absolute deviation of 5 is from the mean of the data set is 28.

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The owner of a bicycle store had a sale on bicycles (two-wheelers) and tricycles (three-wheelers). Each cycle had two pedals. When he counted the total number of pedals of the cycles, he got 50. When he counted the total number of wheels of the cycles, he got 64. Explain how you figured out how many tricycles were offered in the sale.

Answers

Let x represent number of bicycles and y represent number of tricycles.

We know that a bicycle has 2 pedals and a tricycle has 32 pedals as well.

We have been given that when the owner counted the total number of pedals of the cycles, he got 50. We can represent this information in an equation as:

[tex]2x+2y=50...(1)[/tex]

[tex]2x=50-2y...(1)[/tex]

We know that a bicycle has 2 wheels and a tricycle has 3 wheels.

We have been given that when the owner counted the total number of wheels of the cycles, he got 64. We can represent this information in an equation as:

[tex]2x+3y=64...(2)[/tex]

Upon substituting equation (1) in equation (2), we will get:

[tex]50-2y+3y=64[/tex]

[tex]50+y=64[/tex]

[tex]50-50+y=64-50[/tex]

[tex]y=14[/tex]

Therefore, 14 tricycles were offered in the sale.

Sebastian got estimates from 7 companies for his kitchen remodel: $ 27,500 ; $31,000 ; $36,000 ; $92, 000; $29,000 ; $30,500 ; $28,500. Which measure of center best describe the data, is it the mean or the median?

Answers

We have been given that Sebastian got estimates from 7 companies for his kitchen remodel: $ 27,500 ; $31,000 ; $36,000 ; $92,000; $29,000 ; $30,500 ; $28,500. We are asked to find the best measure of center for the given data.

We can see that our given data set has a large valued data point that is $92,000.

We know that mean is very much affected by large valued outliers. The data point $92,000 will increase the mean. Therefore, mean is not a best measure of center for given data.

We know that median is very less affected by outliers, therefore, median will be best measure of center for the given data.

A researcher developing scanners to search for hidden weapons at airports has failed to conclude that a new scanner is significantly better than the current scanner. He made his decision based on a test using alpha equals 0.025 . Would he have made the same decision at alpha equals 0.10 question mark How about alpha equals 0.01 question mark Explain.

Answers

Answer:

Yes, he would take the same decision.

Step-by-step explanation:

Consequently, because the decision is taken on the test based on the use of alpha equals 0.025, the p-value of the test must have been greater than the given amount of importance that is 0.025 since the test is not applicable to us. So, p > 0.025.

If we know that p > 0.025, that would not mean p > 0.1 as well, because we do not know with the details given he had to make the same decision for 0.1 degree of meaning.

As for the 0.01 significance point, we 're sure p > 0.01 is greater than 0.025, so the test does not matter.


use the figure to help you explain the statement

The base(b) of a triangle is ----------inches

The height (h) of the triangle is--------inches

The area of a triangle is ------- Square inches

The area of the rectangle is ------ Square centimeters

help fassstttt

Answers

Step-by-step explanation:

base is 6 in

height is 4 in

to get the area of a triangle is 1/2base×height

being 1/2(6)(4)=12

to get the area of a rectangle is length×width being 9×8=72

By observing the given figure,

The base(b) of a triangle is 6 inches

The height(h)  of  a triangle is 4 inches

The area of the triangle is 12 square inches

The area of the rectangle is 72 square centimeter

What is Triangle?

A triangle is a polygon with three edges and three vertices

What is Rectangle?

A rectangle is a quadrilateral with four right angles

What is Area?

Area is the quantity that expresses the extent of a region on the plane or on a curved surface

From the given figure

The base(b) of a triangle is 6 inches

The height(h)  of  a triangle is 4 inches

The area of a triangle = [tex]\frac{1}{2}bh[/tex]

=[tex]\frac{1}{2}(6)(4)[/tex]

=12 square inches

Length of the rectangle = 8 centimeter

Width of the rectangle = 9 centimeter

Area of the rectangle = l × w = 9×8=72 square centimeter

Hence,

The base(b) of a triangle is 6 inches

The height(h)  of  a triangle is 4 inches

The area of the triangle is 12 square inches

The area of the rectangle is 72 square centimeter

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The what of a figure is a measurement of the space inside it

Answers

Answer: It would be area, because it involves multiplying length by width, therefore covering the inside

Step-by-step explanation:

Hummingbird migrate across the gulf of Mexico. If the distance across the gulf Mexico is about 525 miles and hummingbird fly at a speed of 25 miles per hour, how long does it take a hummingbird to cross the gulf of Mexico

Answers

Answer:

21 hrs

Step-by-step explanation:

Time = D/S

Time=525 m /25 m/h

Time 21 hrs

Answer: 21 hours.

Step-by-step explanation:

25m  = 525

m = 21

In simple linear regression: A The existence of a surrogate variable can explain why two variables have an association without having a causal relationship. B A simple linear regression analysis can prove that there is a causal relationship between two variables. C Both of the above. D Neither of the above.

Answers

Answer:

B. A simple linear regression analysis can prove that there is a causal relationship between two variables.

Step-by-step explanation:

In statistics, a simple linear regression is a method to obtain a formula that helps to predict the values of one variable from another, where there exists a causal behavior. Specifically, through this method, we can say if there's a relation at all, if the correlation is positive or negative, if it's strong or weak.

Therefore, the right answer is B.

Three black beads, two red beads, and a yellow bead are arranged in a line. What is the probability that no black bead is adjacent to the yellow bead?

Answers

Answer:

Probability of no black bead is adjacent to the yellow bead is = 0.966

Step-by-step explanation:

First to arrange all the beads without restrictions = 6! = 720

Probability the black bead is adjacent to Yellow bead = 4!/6! = 24 /720

= 0.0333

Probability of no black bead is adjacent to the yellow bead is

= 1- Probability the black bead is adjacent to Yellow bead

= 1-0.033

= 0.966

WILL MARK BRAINLIEST!
I thought of a three-digit number. If I add all the possible two-digit numbers made by using only the digits of this number, then one third of this sum is equal to the number I thought of. What is the number I thought of?

Answers

Answer:

198

Step-by-step explanation:

If you add 11,18, 19, 81, 88, 89, 91, 98, 99 then the sum would be 594 then dividing by 3 would be 198.

PLZ MARK BRAINLIEST!!!

198 is the anser. ⁂⁂⁂⁂⁂⁂ஐஐஐஐ㋡㋡ஐ㋡㋡㋡㋡㋡ஐ㋡㋡ஐஐஐ㋡㋡㋡ஐஐ㋡㋡✎㋡㋡㋡ஐ✎✎

What is the point slope form of a line that has a slope of 1/2 and passes through point -7, two

Answers

Answer:

y-2=1/2(x+7)

Step-by-step explanation:

Point slope form:

y − y1 = m(x − x1)

We have the coordinate (-7, 2) and slope aka m (1/2)

y-2=1/2(x+7)

Hope this helps! Please mark brainliest :)

Write the expanded form of h(3k-12.4)

Answers

Answer:3hk - 12.4h

Step-by-step explanation:

h(3k-12.4)

h x 3k - h x 12.4

3hk - 12.4h

25 POINTS IF YOU GET THIS ONE RIGHT! VERY HARD

Answers

Answer:1.A 2.C 3.A 4.B

Step-by-step explanation:

1. (answer) a- 257 grams.

2. (answer) c. 1.18 kilometers.

3. (answer) b. 56.

4. (answer) a. 14 7/8 pounds.

What is the exact value of cos -5pi/12

Answers

Answer:

1.00 (2 decimal places)

Answer: sqrt 2(sqrt3 -1)/4

Step-by-step explanation:

ap3x


Alex and Micah scored a total of 40 points in the basketball game. Micah scored four more points than twice Alex's score. How many points did Micah score?
a. 10 points
B. 28 points
C. 12 points
D. 22 points​

Answers

Answer: D

Step-by-step explanation:

 2x + (2x +4 ) =40

x= 9

2(9) +4 =22

15. When coffee is packed by machine into 16-ounce cans, the amount can vary. The mean weight is 16.1 ounces and the standard deviation is 0.04 ounce. The weight of the coffee approximates a normal distribution. a. What percent of the cans of coffee can be expected to contain less than 16 ounces of coffee

Answers

TBH i found it online because im not that smart but the answer is

.6 %

and if the online question is correct there is another question connected to the question you asked, which the answer is 98.8%

can u pls gimme brainly?

guys i really need your help i have this awesome friend who is cool sometimes but she calls me names and pretends to like me bottom line is: is she really my friend


#cryingmyeyesoutrn

Answers

If she calls you name it isn’t very nice and If she pretends to like you than she ain’t a very good friend

Answer:

No. If your being treated like trash and are constantly being called names, talk to your parents or someone, they can help. It's up to you to decide. There are many websites with great advice.

Step-by-step explanation:

(7.8×10^-5)-(4.5×10^-5)​

Answers

Answer:

0.000033

Step-by-step explanation:

​​(7.8×10^-5)-(4.5×10^-5)​=

(7.8×0.00001)-(4.5×0.00001)=

0.000078-0.000045=

0.000033

Answer:

0.000033

Step-by-step explanation:

your welcome :)

How many possible outcomes are there when spinning a spinner numbered from 1 to 8 and tossing a coin?

Answers

Answer:

16

Step-by-step explanation:

From the spinner there are 8 possible outcomes (1 to 8)

From the coin, there 2 (heads or tails)

8*2=16

There are 16 possible outcomes, when spinning a spinner numbered from 1 to 8 and tossing a coin.

What is the fundamental principle of multiplication?

Multiplication is the mathematical operation that is used to determine the product of two or more numbers. If an event can occur in m different ways and if following it, a second event can occur in n different ways, then the two events in succession can occur in m × n different ways.

WE need to find the possible outcomes are there when spinning a spinner numbered from 1 to 8 and tossing a coin.

From the spinner, there are 8 possible outcomes (1 to 8)

From the coin, there 2 heads or tails;

8 x 2 = 16

Hence, There are 16 possible outcomes, when spinning a spinner numbered from 1 to 8 and tossing a coin.

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Gina can write 3 pages per hour. Emily can write 5 pages per hour. If they both write for n number of hours, how many pages will they write altogether?

Answers

Answer:

3n+5n

Step-by-step explanation:

8 pages an hour

Answer:

8n hours.

Step-by-step explanation:

Working together they can write 3+5 = 8 pages per hour.

So the answer is 8 * n hours.

The amount of time a certain brand of light bulb lasts is normally distributed with a mean of 1400 hours and a standard deviation of 75 hours. What is the probability that a randomly chosen light bulb will last less than 1380 hours, to the nearest thousandth?

Answers

Answer:

0.394 = 39.4% probability that a randomly chosen light bulb will last less than 1380 hours

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this question, we have that:

[tex]\mu = 1400, \sigma = 75[/tex]

What is the probability that a randomly chosen light bulb will last less than 1380 hours, to the nearest thousandth?

This is the pvalue of Z when X = 1380. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{1380 - 1400}{75}[/tex]

[tex]Z = -0.27[/tex]

[tex]Z = -0.27[/tex] has a pvalue of 0.394

0.394 = 39.4% probability that a randomly chosen light bulb will last less than 1380 hours

Other Questions
Suppose the round-trip airfare between Philadelphia and Los Angeles a month before the departure date follows the normal probability distribution with a mean of $387.20 and a standard deviation of $68.50. What is the probability that a randomly selected airfare between these two cities will be between $325 and $425? what statement describes the structural characteristic of the poems? Biogeochemical cycles _______. A radio station is giving away tickets to a game. They are giving 2types of tickets: Front seats tickets cost 20 dollars and middle seatstickets cost 10 dollars. They want to give away atleast 20 tickets.But the total cost shouldn't be more than 280 dollarsWrite a system of two inequalities that describes this situation.Let x = number of $10 tickets and y = number of $20 tickets.[A]Graph the system to show all possible outcomes.[B]Write one possible solution to the problem in sentence form. A month of the year is chosen at random. What is the probability that the month starts with the letter J or the letter M?5/241/61/4 5/12 How do we create stronger evidence? A) better observations B) better opinions C) better theories D) better inference the total amount of fiber (in grams) in a package containing x apples and y oranges is given by the equation 5x + 10y = 110. is it possible for the package to contain 15 apples? EXPLAIN 25 POINTS IF YOU GET THIS ONE RIGHT! VERY HARD Solve the system of equations and choose the correct ordered pair.3x+2y= 126x + 3y = 21A. (3,2)B. (4.0)C. (4,3)D. 2, 3) Sebastian got estimates from 7 companies for his kitchen remodel: $ 27,500 ; $31,000 ; $36,000 ; $92, 000; $29,000 ; $30,500 ; $28,500. Which measure of center best describe the data, is it the mean or the median? 43 POINTS AND WILL MARK AS BRAINLIESTRead the following excerpt and pay close attention to the words the author uses:Those who came before us made certain that this country rode the first waves of the industrial revolution, the first waves of modern invention, and the first wave of nuclear power, and this generation does not intend to founder in the backwash of the coming age of space. We mean to be a part of it--we mean to lead it. For the eyes of the world now look into space, to the moon and to the planets beyond. We have vowed that we shall not see it governed by a hostile flag of conquest, but by a banner of freedom and peace. We have vowed that we shall not see space filled with weapons of mass destruction, but with instruments of knowledge and understanding.In a paragraph of four to six sentences, identify three words or phrases with positive connotations and explain how these words influence the paragraph. Be sure to specifically answer the following questions in your response: What images or ideas are associated with each word? How do these words influence the meaning and tone of this passage? Use proper spelling and grammar in your response. Which value has an absolute deviation of 5 from the mean of this data set?26, 12, 35, 28, 14A 28B. 35C. 26D. 14 Factor x^3 - 4x^2 + 7x - 28 by grouping. What is the resulting expression Simplify.Remove all perfect squares from inside the square root.\sqrt{175}= find the solutions to the equation (-3y)(6y)+9=0 Please help me with those questions please please help chose the sentence that best describes an antonym as a context clue to clarify the meaning of the italicized words All systems of the body are important and carry a different function for usto be healthy. Choose ONE from the 8 systems and briefly explain what you can do to help support its functioncan do to help support its function. What lead to the distancing of the enployee and the employer How many milliliters of 0.200 M NH4OH are needed to react with 12.0 mL of 0.550 M FeCl3?FeCl3 + 3NH4OH Fe(OH)3 + 3NH4Cl