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
This topic has expert replies

 Moderator
 Posts: 2207
 Joined: Sun Oct 15, 2017 1:50 pm
 Followed by:6 members
Timer
00:00
Your Answer
A
B
C
D
E
Global Stats
GMAT/MBA Expert
 Brent@GMATPrepNow
 GMAT Instructor
 Posts: 16207
 Joined: Mon Dec 08, 2008 6:26 pm
 Location: Vancouver, BC
 Thanked: 5254 times
 Followed by:1268 members
 GMAT Score:770
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

 Master  Next Rank: 500 Posts
 Posts: 415
 Joined: Thu Oct 15, 2009 11:52 am
 Thanked: 27 times
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
GMAT/MBA Expert
 Scott@TargetTestPrep
 GMAT Instructor
 Posts: 7243
 Joined: Sat Apr 25, 2015 10:56 am
 Location: Los Angeles, CA
 Thanked: 43 times
 Followed by:29 members
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
Scott WoodburyStewart
Founder and CEO
[email protected]
See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews