John and Mary were each paid \(x\) dollars in advance to do

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Official Guide

John and Mary were each paid \(x\) dollars in advance to do a certain job together. John worked on the job for 10 hours and mary worked for 2 hours less than John. If Mary gave John \(y\) dollars of her payment so that they would have received the same hourly wage, what was the dollar amount, in terms of \(y\), that John was paid in advance?

A. \(4y\)
B. \(5y\)
C. \(6y\)
D. \(8y\)
E. \(9y\)

OA E
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by GMATGuruNY » Wed Jul 31, 2019 9:03 am
AAPL wrote:Official Guide

John and Mary were each paid \(x\) dollars in advance to do a certain job together. John worked on the job for 10 hours and mary worked for 2 hours less than John. If Mary gave John \(y\) dollars of her payment so that they would have received the same hourly wage, what was the dollar amount, in terms of \(y\), that John was paid in advance?

A. \(4y\)
B. \(5y\)
C. \(6y\)
D. \(8y\)
E. \(9y\)
Hourly wage = (total pay)/(total number of work-hours)

John worked on the job for 10 hours, and Mary worked for 2 hours less than John.
Thus, the total number of work-hours = 10+8 = 18.

John and Mary were each paid \(x\) dollars in advance.
Since the total pay should be divisible by the total number of work hours, let x = 18.
Since John and Mary are each paid $18 in advance, the total pay = 18+18 = 36.
Thus, the hourly wage = (total pay)/(total number of work-hours) = 36/18 = $2 per hour.

Since John works for 10 hours at a rate of $2 per hour, John's take-home pay = 10*2 = 20.
Since Mary works for 8 hours at a rate of $2 per hour, Mary's take-home pay = 8*2 = 16.

Mary gave John \(y\) dollars of her payment.
Since Mary is given $18 in advance but takes home $16, she gives John $2, implying that y=2.

What was the dollar amount, in terms of y, that John was paid in advance?
Since John was paid $18 in advance, the correct answer must yield 18 when y=2.
Only E works:
9y = 9*2 = 18

The correct answer is E.
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by Scott@TargetTestPrep » Mon Aug 05, 2019 4:10 pm
AAPL wrote:Official Guide

John and Mary were each paid \(x\) dollars in advance to do a certain job together. John worked on the job for 10 hours and mary worked for 2 hours less than John. If Mary gave John \(y\) dollars of her payment so that they would have received the same hourly wage, what was the dollar amount, in terms of \(y\), that John was paid in advance?

A. \(4y\)
B. \(5y\)
C. \(6y\)
D. \(8y\)
E. \(9y\)

OA E
We are first given that John worked for 10 hours and that Mary worked for 2 hours less than John. It follows that:

John's hours = 10

Mary's hours = 8

We are also given that John and Mary were each given x dollars in advance. We are also told that Mary gave John y dollars of her payment so that they would have an equal hourly wage. It follows that Mary actually made x - y dollars. Since John received y dollars, he now made x + y dollars. Using this information, the hourly wages of John and Mary are:

hourly wage = (total paid)/(# of hours)

Mary's wage = (x - y)/8

John's wage = (x + y)/10

Since we are told that the two hourly wages are the same, we can set the hourly wages of John and Mary equal to each other.

(x + y)/10 = (x - y)/8

We can cross multiply and solve:

8x + 8y = 10x - 10y

-2x = -18y

x = 9y

Answer: E

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by Brent@GMATPrepNow » Mon Aug 05, 2019 4:16 pm
AAPL wrote:Official Guide

John and Mary were each paid \(x\) dollars in advance to do a certain job together. John worked on the job for 10 hours and mary worked for 2 hours less than John. If Mary gave John \(y\) dollars of her payment so that they would have received the same hourly wage, what was the dollar amount, in terms of \(y\), that John was paid in advance?

A. \(4y\)
B. \(5y\)
C. \(6y\)
D. \(8y\)
E. \(9y\)

OA E
Salary
Mary's NET salary was x - y dollars (because Mary gave John y dollars)
John's NET salary was x + y dollars

Hours worked
Mary worked 8 hours
John worked 10 hours


In the end, John and Mary received the SAME hourly wage.
So, John's hourly wage = Mary's hourly wage
Hourly wage = (total salary)/(hours worked)
So, (x + y)/10 = (x - y)/8

In terms of y, that John was paid in advance?
In other words, what is the value of x (in terms of y)
So, we'll solve our equation for x.

Take (x + y)/10 = (x - y)/8 and cross multiply to get:
10(x - y) = 8(x + y)
Expand: 10x - 10y = 8x + 8y
Rearrange: 2x = 18y
Divide by 2: x = 9y
So, John's advance payment = x = 9y

Answer: E

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