Comparing fractions

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Comparing fractions

by Cheese12 » Sat Oct 22, 2011 9:16 am
Which of the following fractions is at least twice greater than 11/50?
2/5
11/34
43/99
8/21
9/20


OA: E


whats the best way to do this... i tried to use Bow tie method.. but since the question asks for "double" .. i dont think this is the best way to do it..
pls help !!.. thanks! :)
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by Amiable Scholar » Sat Oct 22, 2011 10:06 am
atleast twice greater than 11/50 = greater then 2*11/50 = greater then 11/25

here you can see 2/5 , 9/20 have 5 and 20 in denominator [5's multiple, easy to make denominator common in comapring fractions] so target them first
now 2/5= 10/25 less then 11/25 . reject
9/20 = 45/100
11/25 = 44/100
45 > 44
so we got the answer here .. :) (E)

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by neelgandham » Sat Oct 22, 2011 1:18 pm
Which of the following fractions is at least twice greater than 11/50?

2/5 = 20/50 < 22/50 so X -- (Multiply numerator and denominator with 10)
11/34 = 22/68 < 22/50 so X -- (Multiply numerator and denominator with 2)
43/99 = Skip !
8/21 = 22/52.5 < 22/50 so X -- (Multiply numerator and denominator with 2.5)
9/20 = 22.5/50 so this is the answer ! -- (Multiply numerator and denominator with 2.5)

OA: E
Anil Gandham
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