It takes an apprentice four times as long as the experienced plumber to replace the pipes under an old house. If it takes them 15 hours when they work together, how long would it take the apprentice alone?

Answer:

Step-by-step explanation:

12 ÷ 2 × 3 − ( 7 − 5 )

= 6 × 3 - 2 (since 7 - 5 = 2)

= 18 - 2

= 16

Answer is C

The value of the expression is 16.

The order of operations, also known as PEMDAS (Parentheses, Exponents, Multiplication and Division, and Addition and Subtraction), is a set of rules used to determine the sequence in which calculations are performed.

In this case, we start with the parentheses first: 7 - 5 = 2. Then, we perform multiplication and division from left to right: 12 ÷ 2 = 6, 6 × 3 = 18. we subtract the result of the parentheses: 18 - 2 = 16. Therefore, the answer is c. 16.

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Answer:

answer choice C

Step-by-step explanation:

The playground is a rectangle.

To find the area of a rectangle, we use the formula:

Area = Length x Width

The length is 25 yards.

The width is 68 yards.

Plugging these into the area formula:

Area = 25 x 68 = 1,700 square yards

Of the options, the closest choice is:

1,710 square yards

The area is 1,710 square yards.

The equation of the line that is parallel to the graph of 2x-3y=7 and contains the point (-3, -3) is expressed as: y = (2/3)x - 1.

To find the equation of a line that is parallel to the graph of 2x - 3y = 7, we need to determine the slope of the given line. We can rewrite the equation in slope-intercept form:

2x - 3y = 7

-3y = -2x + 7

y = (2/3)x - 7/3

This implies that the slope of this line is m = 2/3.

Thus, the equation of the line we are to find will take the following form:

y = (2/3)x + b

where b is the y-intercept of the line.

To find the y-intercept (b), substitute (x, y) = (-3, -3) and m = 2/3 into y = mx + b:

-3 = (2/3)(-3) + b

-3 = -2 + b

b = -1

Substitute m = 2/3 and b = -1 into y = mx + b:

y = (2/3)x - 1

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3.) The volume of the triangular prism = 6,480 mi³

The surface area of the triangular prism = 1,872mi²

To determine the surface area of the given triangular prism, the formula that should be used is given as follows:

Surface area = bH + (b1+b2+b3)×l

where ;

b= 8 mi

b1 = 18 mi

b2 = 24 mi

b3 = 30 mi

Height = 18 mi

length = 24 mi

Surface area = 8×18 + ( 18+24+30)× 24

= 144 + 1728

= 1,872mi²

To calculate the volume of a triangular prism, the formula the should be used is given as follows;

Volume = 1/2 × b× h × L

where;

b = 24 ni

h = 18 mi

l = 30 mi

volume = 1/2 ×24×18×30

= 6,480 mi³

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Answer:

113 or 401: see below for explanation

Step-by-step explanation:

x = 8

The way you wrote it with the " * " symbol, it means the multiplication of 6x and 2. This is what I did in the line below.

6x × 2 + 17 = 6 × 8 × 2 + 17 = 48 × 2 + 17 = 113

If by " * " you actually meant an exponent, such as 6x², then here is the calculation using 2 as an exponent. For exponent, we normally use ^, such as 6x^2 to mean 6x².

6x² + 17 = 6 × 8² + 17 = 6 × 64 + 17 = 384 + 17 = 401

Answer:

∠ a = 125°

Step-by-step explanation:

the measure of chord- chord angle a is half the sum of the measures of the arcs intercepted by the angle and its vertical angle, that is

∠ a = [tex]\frac{117+133}{2}[/tex] = [tex]\frac{250}{2}[/tex] = 125°

To compute the number of 12 letter combinations of the 26 letters in the alphabet, we can use the formula for combinations, which is:

nCr = n! / r!(n-r)!

where n is the total number of items (26 letters in this case), r is the number of items to choose (12 letters in this case), and ! means factorial (the product of all positive integers up to that number).

Using this formula, we can plug in the numbers:

26C12 = 26! / 12!(26-12)!
= (26 x 25 x 24 x 23 x 22 x 21 x 20 x 19 x 18 x 17 x 16 x 15) / (12 x 11 x 10 x 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1)
= 9,675,700

Therefore, there are 9,675,700 possible 12 letter combinations of the 26 letters in the alphabet.

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There is not enough evidence to conclude that Devon's true proportion of good serves is greater than 72%.

The correct conclusion for Devon to reach is: Because the P-value of 0.06 > a (where a = 0.05), Devon should fail to reject H0. There is no convincing evidence that the proportion of services that are good is more than 72%.

The null hypothesis, H0, states that the true proportion of good serves for Devon is equal to 72%. The alternative hypothesis, Ha, states that the true proportion of good serves for Devon is greater than 72%.

The P-value is the probability of obtaining a test statistic as extreme or more extreme than the observed data, assuming that the null hypothesis is true. In this case, the P-value is 0.06, which means that if the true proportion of good serves for Devon is actually 72%, there is a 6% chance of observing a sample of 50 serves with 42 or more good serves.

Since the P-value is greater than the significance level of 0.05, we fail to reject the null hypothesis.  

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The 68% confidence interval for systolic blood pressure in women, based on the given sample, is approximate: (122.77, 124.03)

To find the 68% confidence interval for systolic blood pressure in women, we can use the standard formula:

Confidence Interval = Mean ± (Z * (Standard Deviation / √n))

Where:

Mean = 123.4 (sample mean)

Standard Deviation = 19.9 (sample standard deviation)

n = 1000 (sample size)

Z = Z-score corresponding to the desired confidence level (in this case, 68% corresponds to 1 standard deviation on each side of the mean)

To find the Z-score, we can refer to the standard normal distribution table or use a calculator. For a 68% confidence level, the Z-score is 1.

Plugging in the values, we get:

Confidence Interval = 123.4 ± (1 * (19.9 / √1000))

Calculating the square root of 1000, we have:

Confidence Interval = 123.4 ± (1 * (19.9 / 31.62))

Simplifying further, we get:

Confidence Interval = 123.4 ± (0.6301)

Therefore, the 68% confidence interval for systolic blood pressure in women, based on the given sample, is approximate: (122.77, 124.03).

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The standard deviation of X to be approximately 0.4852. The correct answer is option (A).

To calculate the standard deviation of X, we need to first calculate the probability of drawing a red marble on the first draw, which is 11/29. The probability of not drawing a red marble on the first draw is 18/29. The probability of drawing a red marble on the second draw, given that we did not draw a red marble on the first draw, is 11/29. Using the formula for the geometric distribution, which models the number of trials until the first success, we can calculate the expected value of X, which is 1/p, where p is the probability of success (11/29 in this case).

Therefore, the expected value of X is 29/11. To calculate the standard deviation of X, we use the formula sqrt(q/p^2), where q is the probability of failure (18/29) and p is the probability of success (11/29). Plugging in these values, we get the standard deviation of X to be approximately 0.4852.  Therefore, the correct answer is option A, 0.4852.

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The calculated value of the expression 3 - (-1) + (-1) - 3 using a calculator is 0

From the question, we have the following parameters that can be used in our computation:

The expression 3 - (-1) + (-1) - 3

We can add the numbers using a calculator

So, we have the following representation

Value = 3 - (-1) + (-1) - 3

Using the above as a guide, we have the following:

Value = 0

This means that the value of the expression 3 - (-1) + (-1) - 3 using a calculator is 0

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The volume of the cylinder after the rotation of rectangle is V = 12π units³ = 37.68 units³

Given data ,

Let the width of the rectangle be w = 2 units

Let the length of the rectangle be l = 3 units

Now , on rotating a rectangle , we get a cylinder

And , the radius of the cylinder = 2 units

And , the height of the cylinder = 3 units

Now , Volume of Cylinder = πr²h

On simplifying , we get

V = π ( 2 )² ( 3 )

V = 12π units³

V = 37.68 units³

Hence , the volume of cylinder is V = 37.68 units³

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Answer:

we know that given triangle is right angled triangle.

➢ By using Phythagoras Theorem:-

[tex] \sf \longrightarrow \: (AC)^2 = (AB)^2 + (BC)^2[/tex]

[tex] \sf \longrightarrow \: ( \sqrt{80} )^2 = (x)^2 + (8)^2[/tex]

[tex] \sf \longrightarrow \: 80 = (x)^2 + (8)^2[/tex]

[tex] \sf \longrightarrow \: 80 \: = x^2 \: + \: 8^2[/tex]

[tex] \sf \longrightarrow \: 80 \: = x^2 \: + \: 64[/tex]

[tex] \sf \longrightarrow \: 80 \: - 64 = x^2 \:[/tex]

[tex] \sf \longrightarrow \: 16 = x^2 \:[/tex]

[tex] \sf \longrightarrow \: x^2 \: = 16[/tex]

[tex] \sf \longrightarrow \: x \: = \sqrt{16} [/tex]

[tex] \sf \longrightarrow \: x \: = 4 \: units [/tex]

Answer:

Pe^(.0475 × 20) = $20,000

P = $7,734.82

The basic arithmetic operators (+,-,*,/) are commonly used in formulas to perform mathematical calculations. They are collectively known as "operators" and are an essential component of mathematical formulas, allowing us to perform complex calculations quickly and efficiently.

The symbols mentioned in the question, i.e., (+,-,*,/) are the basic arithmetic operators that are used in mathematical formulas to perform different types of calculations. These symbols are collectively referred to as "operators" or "mathematical operators."

Operators are an essential part of mathematical formulas as they allow us to perform complex mathematical calculations in a concise and efficient manner. They act as a shorthand way of representing mathematical operations and make it easier to perform calculations without having to write out the entire equation every time.

In addition to the basic arithmetic operators mentioned above, there are other types of operators that can be used in formulas depending on the specific mathematical operation being performed. For example, there are logical operators like AND, OR, and NOT that are used in Boolean algebra to perform logical calculations.

Other operators that can be used in formulas include exponentiation (^), which is used to raise a number to a certain power, and modulo (%), which is used to find the remainder when one number is divided by another.

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The population grows by a factor of 2 every year.

The number of fish in a lake is growing exponentially, with given data for different numbers of years since the population was first measured as follows:

Years | Population (in thousands)
0     | 10
1     |
2     | 40
3     |
4     |
5     |
6     |

By what factor does the population grow every two years?
From year 0 to year 2, the population grows from 10,000 to 40,000. To find the growth factor, divide the population in year 2 by the population in year 0:
40,000 ÷ 10,000 = 4.

Thus, the population grows by a factor of 4 every two years.

Using this information, we can calculate the population for years 4 and 6:
Year 4: 40,000 × 4 = 160,000 (160 in thousands)
Year 6: 160,000 × 4 = 640,000 (640 in thousands)

By what factor does the population grow every year?
To find the yearly growth factor, take the square root of the growth factor every two years:
√4 = 2.

Thus, the population grows by a factor of 2 every year.

Using this information, we can complete the table:
Years | Population (in thousands)
0     | 10
1     | 20
2     | 40
3     | 80
4     | 160
5     | 320
6     | 640

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The area of the object is 40 square centimeters

The correct answer is an option (B)

We know that the formula for the area of trapezoid is,

A = ((a + b)/2) × h

where a and b are the two parallel bases

h is the height of the trapezoid

From the attached figure, first we determine the length of the two parallel bases.

Let us assume that 'a' represents the length of the upper base and 'b' represents the length of the bottom side of the trapezoid

We can observe that a = 2x

so the length of a = 6 centimeters

And b = 2z

So, the length of b = 2(5)

                              = 10 cm

Here, the height h of the trapezoid is given by y = 5 cm

Using above formula for the area of trapezoid, the area of the object would be,

A = ((a + b)/2) × h

A = ((6 + 10)/2) × 5

A = (16/2)  × 5

A = 40 cm²

Therefore, the correct answer is an option (B)

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Find the complete question below.

The height of the cone is approximately 3.4 cm.

The formula for the volume of a cone is V = (1/3)πr^2h, where V is the volume, r is the radius, and h is the height.

We are given that the radius of the cone is 3 cm and the volume is 94.2 cm^3. Substituting these values into the formula, we get:

94.2 = (1/3)π(3^2)h

Simplifying:

94.2 = 9πh

h = 94.2 / (9π)

h ≈ 3.4

Therefore, the height of the cone is approximately 3.4 cm.

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The expression that represents the area of the rectangular patio in factored form is: area = [(t + 4)(t + 21) / 2(t + 7)(t + 2)]

An expression is a grouping of numbers, variables, and mathematical operations like addition, subtraction, multiplication, and division in mathematics.

Exponents, functions, and other mathematical symbols may also be included.

In mathematical equations and formulas, expressions are used to represent numbers, calculations, and relationships.

The length of the rectangular patio is given by the expression:

length = (t^2 + 19t + 84) / (4t - 4)

The width of the rectangular patio is given by the expression:

width = (2t - 2) / (t² + 9t + 14)

The area of the rectangular patio is given by the product of its length and width:

area = length x width

By substituting, we get:

area = [(t² + 19t + 84) / (4t - 4)] x [(2t - 2) / (t² + 9t + 14)]

We can factor the numerator and denominator of both fractions to simplify the expression:

area = [(t + 4)(t + 21) / 4(t - 1)] x [2(t - 1) / (t + 7)(t + 2)]

We can then simplify the expression by canceling out the common factors of (t - 1) in the numerator and denominator:

area = [(t + 4)(t + 21) / 4] x [2 / (t + 7)(t + 2)]

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Karen's last class will end at three in the afternoon.

Given that Kevin has three classes in a row, each lasting two hours, we can calculate the total duration of his classes. Three classes, each two hours long, amount to a total of 6 hours.

Since Kevin's first class starts at seven in the morning, we add 6 hours to that time, resulting in the conclusion of Karen's last class at three in the afternoon.

Understanding schedules and timetables is essential for effective time management. In academic settings, students often have multiple classes with varying durations throughout the day.

Calculating the end time of a class or event based on its start time and duration helps individuals plan their activities and allocate their time efficiently.

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The perimeter of the rectangle is 8 1/4 feet. the correct answer is A.

Perimeter is the total length of the sides of a two-dimensional shape. In a rectangle, opposite sides are equal in length, so the perimeter can be found by adding the lengths of all four sides. To find the perimeter of a rectangle, we use the formula:

Perimeter = 2(length + width)

In this case, the length is given as 3 1/4 feet and the width is given as 7/8 feet. To find the perimeter, we substitute these values into the formula:

Perimeter = 2(3 1/4 + 7/8)

To simplify, we need to convert the mixed number to an improper fraction and find a common denominator for the fractions:

Perimeter = 2(13/4 + 7/8)

Perimeter = 2(26/8 + 7/8)

Perimeter = 2(33/8)

Now we can simplify the expression by multiplying 2 by the fraction:

Perimeter = 66/8

We can reduce this fraction by dividing both the numerator and denominator by 2:

Perimeter = 33/4

Therefore, the perimeter of the rectangle is 8 1/4 feet, which is answer choice A.

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The measure of angle x is: x = (3/5)(180 - z) = (3/5)(180 - 90) = 36 degrees

And the measure of angle y is:y = (2/5)(180 - z) = (2/5)(180 - 90) = 24 degrees

Since lines lll, mmm, and nnn are parallel to each other and ppp is a transversal, we can use the angle properties of parallel lines to find the relationship between angle x and angle y.

From the given information, we have:  2x = 3y

Simplifying this equation, we get:  x = (3/2)y

Now, we can use this relationship to find the measures of angles x and y in terms of a common variable. Let's use z as the common variable.

x + y + z = 180 (angles on a straight line)

Substituting x = (3/2)y, we get:  (3/2)y + y + z = 180

Simplifying this equation, we get: (5/2)y + z = 180

Now, we can express y in terms of z:

(5/2)y = 180 - z

y = (2/5)(180 - z)

Similarly, we can express x in terms of z:

x = (3/2)y = (3/2)(2/5)(180 - z) = (3/5)(180 - z)

Now, we can use the relationship between angle x and angle y to find the measure of angle x in terms of z: 2x = 3y

2[(3/5)(180 - z)] = 3[(2/5)(180 - z)]

Simplifying this equation, we get: (6/5)z = 108

z = (5/6)(108) = 90

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To find out how long Sara studied in all, we need to add the time she studied before dinner and after dinner.

Sara studied for 3 1/2 hours before dinner and 45 minutes after dinner.

We can convert 3 1/2 hours to minutes by multiplying it by 60:

3 1/2 hours = 3 × 60 + 30 = 180 + 30 = 210 minutes

So, Sara studied for 210 minutes before dinner and 45 minutes after dinner.

To find the total time, we add these two values:

Total time = 210 minutes + 45 minutes = 255 minutes

Therefore, Sara studied for 255 minutes in all.

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Answer:

Step-by-step explanation:

To prove that the right triangles are congruent, we need to show that they have three pairs of congruent parts (sides or angles).

Let's say that the given congruent parts are the hypotenuses and one leg of each triangle. To prove congruence, we can add one more pair of congruent parts, such as the other leg.

By the Side-Angle-Side (SAS) congruence theorem, if two triangles have two pairs of congruent sides and the included angle is also congruent, then the triangles are congruent. In this case, we have two pairs of congruent sides (the hypotenuses and one leg) and the included angle (the right angle) is congruent by definition.

Therefore, we can conclude that the two right triangles are congruent by SAS.

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Answer:

The mean would decrease in value to about 17.1 inches.

Step-by-step explanation:

If we add a smaller data to the mean of a numerical data set, the mean will decrease.

Hope this helps.

The median number of goals scored is 1, and the mean number of goals scored is 2. The median is less than the mean, indicating a right-skewed distribution.

To find the median, we need to first put the numbers in order

0, 0, 1, 1, 1, 3, 3, 4, 5

There are an odd number of values, so the median is the middle value, which is 1.

To find the mean, we add up all the values and divide by the number of values

(0 + 0 + 1 + 1 + 1 + 3 + 3 + 4 + 5) / 9 = 2

So the mean number of goals scored is 2.

Since the median (1) is less than the mean (2), we can say that the distribution is skewed to the right. This is because the high value of 5 pulls the mean up, while the median is not affected as much by outliers.

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To multiply the polynomials (1-2t)(5t+t^2), we can use the distributive property and multiply each term in the first polynomial by each term in the second polynomial:

(1-2t)(5t+t^2) = 1(5t+t^2) - 2t(5t+t^2)

Multiplying the first term by each term in the second polynomial, we get:

5t + t^2

Multiplying the second term by each term in the second polynomial, we get:

-10t^2 - 2t^3

Combining like terms, we get:

-2t^3 - 10t^2 + 5t

Therefore, the answer is D. -2t^3 - 9t^2 + 5t.

The simplified rational expression for this problem is given as follows:

[tex]\frac{3\sqrt{21} + 13}{12}[/tex]

The rational expression in the context of this problem is defined as follows:

[tex]\frac{\sqrt{7} + \sqrt{3}}{2\sqrt{3} - \sqrt{7}}[/tex]

The first step in simplifying the expression is removing the root from the denominator, multiplying numerator and denominator by the conjugate, as follows:

[tex]\frac{\sqrt{7} + \sqrt{3}}{2\sqrt{3} - \sqrt{7}} \times \frac{2\sqrt{3} + \sqrt{7}}{2\sqrt{3} + \sqrt{7}}[/tex]

Applying the subtraction of perfect squares, the denominator is given as follows:

2² x 3 - 7 = 12.

The numerator is:

[tex](\sqrt{7} + \sqrt{3})(2\sqrt{3} + \sqrt{7}) = 2\sqrt{21} + 7 + 6 + \sqrt{21} = 3\sqrt{21} + 13[/tex]

Thus the simplified expression is:

[tex]\frac{3\sqrt{21} + 13}{12}[/tex]

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