Simple maths question help

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Simple maths question help

by GMAT? » Thu Dec 21, 2006 8:15 am
In a weight lifting competition, the total weight of Joe's two lifts was 750 pounds. If twice the wieght of his first lift was 300 pounds more than the weight of his second lift. What was the weight of his first lift?

Let A be the weight of his first lift:

2A + A + 300 = 750

3A = 1050

A = 350......which is the right answer but I'm unsure whether my working out is correct.

Thanks all.

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by thankont » Thu Dec 21, 2006 9:56 am
A --> 1st. B--> 2nd.
A+B=750
2A=300+B => B=2A-300 subst. into first eqn. so we have
A+2A-300=750 => A=350

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simpler

by bluestocking » Sat Dec 30, 2006 1:05 pm
alternatively

x = first lift
750 - x = second lift

therefore
2x = (750-x) + 300
2x + x = 750 + 300 ----> 3x = 1050

x = 350

helpful hint : try to work with as few variables as possible.