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Less than 1

by heshamelaziry » Fri Aug 28, 2009 10:45 am
If 0<r<1 and 1<s<2, which of the following must be less than 1?

1)r/s
2)r*s
3)s-r

This question seems easy. However OA says 1 ONLY. I say that 2 is correct too.
OA should be 1 and 2.
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by sbasha » Fri Aug 28, 2009 10:59 am
r * s wont be right

r = 0.9
s = 1.9 , in this case r*s >1
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by heshamelaziry » Fri Aug 28, 2009 11:07 am
sbasha wrote:r * s wont be right

r = 0.9
s = 1.9 , in this case r*s >1
For answer 2, almost all other options of numbers will make it less than 1.

How do I try numbers correctly in a minute and 50 seconds ???
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by bharathh » Fri Aug 28, 2009 11:13 am
This is a tough one...

I go for the boundary conditions...

0.1, 0.9, 1.1, 1.9

Try combinations of these 4 values. What is the recommended strategy in terms of what numbers should be tried out for questions such as these?
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by tom4lax » Fri Aug 28, 2009 6:14 pm
Easier to visualize if you work with fractions.

For II) we want to find numbers that dont satisfy the condition of <1.

for what ever number you pick for r, when is it not less than 1, so equal or greater to 1?

r = 3/4
3/4 S = 1
S = 4/3

II is not always True
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