Source: GMAT Paper Tests
If Jake loses \(8\) pounds, he will weigh twice as much as his sister. Together they now weigh \(278\) pounds. What is Jake's present weight, in pounds?
A. \(131\)
B. \(135\)
C. \(139\)
D. \(147\)
E. \(188\)
The OA is E
If Jake loses \(8\) pounds, he will weigh twice as much as his sister. Together they now weigh \(278\) pounds. What is
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Here's a solution that uses one variable.BTGmoderatorLU wrote: ↑Fri Jul 08, 2022 7:54 amSource: GMAT Paper Tests
If Jake loses \(8\) pounds, he will weigh twice as much as his sister. Together they now weigh \(278\) pounds. What is Jake's present weight, in pounds?
A. \(131\)
B. \(135\)
C. \(139\)
D. \(147\)
E. \(188\)
The OA is E
Let x = Jake's present weight in pounds
So, x  8 = Jake's hypothetical weight IF he were to lose 8 pounds
If Jake loses 8 pounds, he will weigh twice as much as his sister.
In other words, the sister weighs HALF as much as Jake's hypothetical weight of x  8 pounds
So, (x  8)/2 = sister's present weight
Together they NOW weigh 278 pounds.
So, Jake's present weight + sister's present weight = 278
So, x + (x  8)/2 = 278
Eliminate the fraction by multiplying both sides by 2 to get: 2x + (x  8) = 556
Simplify: 3x  8 = 556
Add 8 to both sides: 3x = 564
Solve: x = 564/3 = 188
Answer: E

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BTGmoderatorLU wrote: ↑Fri Jul 08, 2022 7:54 amSource: GMAT Paper Tests
If Jake loses \(8\) pounds, he will weigh twice as much as his sister. Together they now weigh \(278\) pounds. What is Jake's present weight, in pounds?
A. \(131\)
B. \(135\)
C. \(139\)
D. \(147\)
E. \(188\)
The OA is E
This is the same thing as saying that if you subtract 8 from the appropriate answer choice the result will be a multiple of 2 and thus even.
Answer choices A,B,C and D are odd numbers that will result in an odd number if the even number 8 is subtracted from them, therefore the answer must be E,188
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 Scott@TargetTestPrep
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We let J = Jake’s current weight and S = Sister’s current weight, in pounds, and create the equations:BTGmoderatorLU wrote: ↑Fri Jul 08, 2022 7:54 amSource: GMAT Paper Tests
If Jake loses \(8\) pounds, he will weigh twice as much as his sister. Together they now weigh \(278\) pounds. What is Jake's present weight, in pounds?
A. \(131\)
B. \(135\)
C. \(139\)
D. \(147\)
E. \(188\)
The OA is E
J – 8 = 2S
J = 2S + 8 (Equation 1)
and
J + S = 278 (Equation 2)
To solve this equation, we can substitute 2S + 8 from Equation 1 for the variable J in Equation 2:
(2S + 8) + S = 278
3S = 270
S = 90
We now know that the sister weighs S = 90 pounds, and we can plug that value into either equation to determine J. Let’s plug 90 for S into equation 2:
J + 90 = 278
J = 188
Answer: E
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