Word problems which have comparisons using words like "As old as"

Question

Hey!

Can someone help me to get is correct, once and for all. Most of the times I make mistakes in word problems which give comparison using words such as "As much as" or "As old As". Kindly suggest a convenient way to get this right most of the times.

Question such as this: Today Bill is thirteen times as old as Pete. In nine years Bill's age will be 4 times as old as Pete. how old will pete be in Pete in two years

Thanks,
:arrow:

Ani

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Ani

OptimusPrepJanielle · Answer

Hi anirudhmehra,

I am not sure what you are asking. Can you please elaborate the question?
If you asking about the meaning of "As much as" or "As old As", they both mean the multiplication factor between two things or can be used to say that things are equal.
For example: Bill is as old as Pete. or Bill earns as much money as Pete earns.
In both these cases, the things in consideration are equal.

In the stated problem, it says: 
Bill is thirteen times as old as Pete
This simply means that B = 13P

In nine years Bill's age will be 4 times as old as Pete
This means B + 9 = 4(P+9)

Does this help?

EMPOWERgmatRichC · Answer

Hi anirudhmehra,

You would likely receive more of a response if you posted this in the Quant PS Forum here:

gmat-problem-solving-ps-140/

While this question can be solved algebraically, it can also be solved by TESTing THE ANSWERS.

The prompt asks for how old Pete will be IN 2 YEARS. By subtracting 2 from each of the answer choices, we have the 5 options for how old Pete is NOW (1, 2, 3, 4 or 5). From there, we would just have to find the number that mathematically 'fits' with all of the information that we've been given.

IF...
Pete is NOW = 3
Bill is NOW = 13(3) = 39

In 9 years...
Pete = 12
Bill = 48
Bill is 4 times as old as Pete (which matches what we were told).

Thus, Pete IS now 3, and in two years would be 5.

Final Answer:

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C

GMAT assassins aren't born, they're made,
Rich

anirudhmehra · Answer

Thanks Janielle,

Your description to what I've asked above is correct, however, in few of the solutions many people have mentioned the first equation to be "13B=P"
 & the second equation is same as yours. This actually got me confused.

This is why I primarily asked for the equality "As much as" because of the ambiguity in the solution provided on other blogs.

Word problems which have comparisons using words like "As old as"

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