If x + y = 8z, then which of the following represents the average

Question

If x + y = 8z, then which of the following represents the average (arithmetic mean) of x, y, and z, in terms of z ?

(A) 2z + 1
(B) 3z
(C) 5z
(D) z/3
(E) 3z/2

Bunuel · Accepted Answer

SOLUTION

If x + y= 8z, then which of the following represents the average (arithmetic mean) of x, y, and z, in terms of z ?

(A) 2z + 1
(B) 3z
(C) 5z
(D) z/3
(E) 3z/2

The average of x, y and z equals to (x+y+z)/3 as x+y=8z then (x+y+)z/3=(8z+z)/3=9z/3=3z.

Answer: B.

BrentGMATPrepNow · Answer

Here's a solution that involves the INPUT-OUTPUT approach.

Given: x + y = 8z
So, one possible solution to this equation is x = 7, y = 9 and z =  2

Which of the following represents the average (arithmetic mean) of x, y, and z, in terms of z?  
Average = (x + y + z)/2
= (7 + 9 + 2)/2
= 18/3
=  6

So, when we INPUT  x = 2 , the answer to the question is  6 
So, we're looking for an answer choice that OUTPUTS a  6  when we INPUT  x = 2 
Let's check the answer choices...

(A) 2( 2 ) + 1 =  5 . No good. We want  6 . ELIMINATE
(B) 3( 2 ) =  6 . KEEP
(C) 5( 2 ) =  10 . No good. We want  6 . ELIMINATE
(D)  2 /3 =  2/3 . No good. We want  6 . ELIMINATE
(E) 3( 2 )/2 =  3 . No good. We want  6 . ELIMINATE

Answer: B

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AKG1593 · Answer

Option B.
Average of x,y and z=>(x+y+z)/3
x+y=8z(given)
Replacing we get,9z/3=3z

bharatdivvela · Answer

Average of x,y,z is (x+y+z)/3=(8z+z)/3=3z

OptimusPrepJanielle · Answer

AM of x, y, z = (x+y+z)/3 = (8z+z)/3 = 3z

Correct Option: B

vikasp99 · Answer

x+y=8z then (x+y+)z/3=(8z+z)/3=9z/3=3z.

ScottTargetTestPrep · Answer

We need to determine the average of x, y, and z. In other words:

(x + y + z)/3 = ?

Since x + y = 8z, we can substitute 8z for x + y in our average formula and we have:

(8z + z)/3 = 9z/3 = 3z

Answer: B

ArnauG · Answer

To find the average of x, y, and z in terms of z, we can use the formula for the average of three numbers.

The average is found by summing the numbers and then dividing the sum by the count of numbers. In this case, we have x, y, and z.

Given that x + y = 8z, we can rearrange the equation to solve for y:

y = 8z - x.

Now, let's calculate the average of x, y, and z:

Average = (x + y + z) / 3.

Substituting the value of y from the equation above, we have:

Average = (x + (8z - x) + z) / 3.

Simplifying this expression, we get:

Average = (8z + z) / 3.

Combining like terms, we have:

Average = 9z / 3.

Simplifying further, we get:

Average = 3z.

Therefore, the average of x, y, and z in terms of z is (B) 3z.

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If x + y = 8z, then which of the following represents the average

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If x + y = 8z, then which of the following represents the average

Prep Toolkit

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