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xerocoool
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Q34) Manhattan 5lbs : Fractions & Decimals

by xerocoool Wed Aug 27, 2014 11:53 pm

Q) 4/5 of the women and 3/4 of the men speak Spanish. If there are 40% as many men as women, what fraction of the group speaks Spanish ?

Need to plug in answer into the fraction box.

My doubt is if we consider,

M = 40% Women
Say W = 100
M = 40

Solving this we get "11/14 or equivalent form" (which is the answer given behind)

But if we consider,
W = 200
M = 80
(4/5) of 200 = 160
(3/5) of 80 = 48

Fraction of group speaking Spanish = 208/280 = 26/25

Why this ambiguity ?

Thanks
x
tommywallach
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Re: Q34) Manhattan 5lbs : Fractions & Decimals

by tommywallach Fri Aug 29, 2014 1:20 pm

Hey Xero,

Something that's true for one set of numbers will of course be true for all numbers. If this ever happens to you, you must have screwed up the arithmetic somewhere. Just keep checking your work. It's better practice to find the error yourself than to have it pointed out. In this case:

But if we consider,
W = 200
M = 80
(4/5) of 200 = 160
(3/5) of 80 = 48

See the problem? The question said 3/4, not 3/5.

-t
xerocoool
Students
 
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Re: Q34) Manhattan 5lbs : Fractions & Decimals

by xerocoool Fri Aug 29, 2014 1:58 pm

Ah ! I've been interpreting a lot of questions wrong lately. Apologize for the mistake.

Will double check before posting hence forth :)

Thanks for pointing out.

-xero
tommywallach
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Re: Q34) Manhattan 5lbs : Fractions & Decimals

by tommywallach Wed Sep 03, 2014 8:11 pm

No worries! Please don't take that as a criticism; just a recommendation. "Silly" errors are super deadly on the GRE, so it's always important to have a method in place for learning to make fewer of them. One way is to recognize that a given answer could ONLY be wrong because of a silly mistake (i.e. if it's just an arithmetic or algebra question yet you end up with an answer not in the choices).

Good luck with it!
xerocoool
Students
 
Posts: 63
Joined: Fri Aug 24, 2012 9:54 am
 

Re: Q34) Manhattan 5lbs : Fractions & Decimals

by xerocoool Thu Sep 04, 2014 5:12 pm

roger ! :)
tommywallach
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Re: Q34) Manhattan 5lbs : Fractions & Decimals

by tommywallach Mon Sep 08, 2014 8:37 pm

: )