in a weight-lifiting competition, the total weight of Joe's two lifts was 750 pounds. If twice the weight of his first lift was 300 pounds more than the weight of his second lift, what was the weight in pounds, of his first lift?
A.225
B.275
C.325
D.350
E.400
How could you solve this problem by backsolving??
D
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Weight Lifting
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Why do you want to back solve this? This is very straight forward. Set up your equations, S cancels out and you are left with F. Back solving may even be harder.deepoe wrote:in a weight-lifiting competition, the total weight of Joe's two lifts was 750 pounds. If twice the weight of his first lift was 300 pounds more than the weight of his second lift, what was the weight in pounds, of his first lift?
A.225
B.275
C.325
D.350
E.400
How could you solve this problem by backsolving??
D
2F-S=300
F +S =750
3F=1050
F=350.
In 20 seconds you solve this.
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Solution:deepoe wrote:in a weight-lifiting competition, the total weight of Joe's two lifts was 750 pounds. If twice the weight of his first lift was 300 pounds more than the weight of his second lift, what was the weight in pounds, of his first lift?
A.225
B.275
C.325
D.350
E.400
How could you solve this problem by backsolving??
D
This problem is a general word translation. We first define variables and then set up equations.
We can define the following variables:
F = the weight of the first lift
S = the weight of the second lift
We are given that the total weight of Joe's two lifts was 750 pounds. We sum the two variables to obtain:
F + S = 750
We are also given that twice the weight of his first lift was 300 pounds more than the weight of his second lift. We express this as:
2F = 300 + S
2F - 300 = S
We can now substitute (2F - 300) for S into the first equation, so we have:
F + 2F - 300 = 750
3F = 1,050
F = 350
Answer: D
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Brent@GMATPrepNow
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We can also solve the question using ONE VARIABLE.deepoe wrote:in a weight-lifiting competition, the total weight of Joe's two lifts was 750 pounds. If twice the weight of his first lift was 300 pounds more than the weight of his second lift, what was the weight in pounds, of his first lift?
A.225
B.275
C.325
D.350
E.400
The total weight of Joe's two lifts was 750 pounds.
Let x = weight of first lift
So, 750 - x = weight of second lift
...twice the weight of his first lift was 300 pounds more than the weight of his second lift
In other words, (2)(first lift) = second lift + 300
Or...(2)(x) = (750 - x) + 300
Simplify: 2x = 1050 - x
Rearrange: 3x = 1050
x = 350
Answer: D
Cheers,
Brent
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DavidG@VeritasPrep
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This thread is from 2009. Deepoe has been waiting six years for his back-solving solution!In a weight-lifiting competition, the total weight of Joe's two lifts was 750 pounds. If twice the weight of his first lift was 300 pounds more than the weight of his second lift, what was the weight in pounds, of his first lift?
A.225
B.275
C.325
D.350
E.400
How could you solve this problem by backsolving??
Well, I see that his total weight for the two lifts was 750, so scanning the answer choices, 350, will be the easiest to test. If his first lift was 350, the second lift was 750 - 350, or 400. I'm told that if I double his first lift, it should be 300 more than the second lift. Sure enough double the first lift is 350 *2 = 700, which is 300 more than the second lift. Answer is D.
Rest easy, Deepoe.
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Brent@GMATPrepNow
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July 7, 2015: Deepoe awakens to see that someone FINALLY answered his question about a back-solving solution.DavidG@VeritasPrep wrote: This thread is from 2009. Deepoe has been waiting six years for his back-solving solution!
After reviewing the solution, he promptly schedules his test for the next day and scores an unprecedented 801!
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DavidG@VeritasPrep
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Glad to see this emotional saga has such a satisfying endingJuly 7, 2015: Deepoe awakens to see that someone FINALLY answered his question about a back-solving solution.
After reviewing the solution, he promptly schedules his test for the next day and scores an unprecedented 801!
Movie rights?GMAT/MBA Expert
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Brent@GMATPrepNow
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Agreed!DavidG@VeritasPrep wrote: Glad to see this emotional saga has such a satisfying ending
I was thinking of something along the line of a televised mini-series, with cross-promotional deals for action figures, video games and, of course, breakfast cerealDavidG@VeritasPrep wrote:
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