Inequalities

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Inequalities

by beater » Thu Oct 02, 2008 3:07 pm
If n > 0, which is greater, 20 percent of n or 10 percent of the sum of n and 0.5 ?
(1) n < 0.1
(2) n > 0.01

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by namitrajiv » Thu Oct 02, 2008 3:37 pm

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Re: Inequalities

by Morgoth » Thu Oct 02, 2008 6:22 pm
beater wrote:If n > 0, which is greater, 20 percent of n or 10 percent of the sum of n and 0.5 ?
(1) n < 0.1
(2) n > 0.01
n>0
which one is greater n/5 or (n+0.5)/10

For any value of n>1 it is not hard to see that n/5 will always be greater.

statement (1)
n<0.1
n<1/10

let n=1/20
n/5 = 1/100=2/200

(n+0.5)/10 = (1/20+5/10)/10 = 11/200

2/200 < 11/200
n/5 < (n+0.5)/10

let n=2/100

n/5<(n+0.5)/10
Sufficient.

Statement (2)
n=1/100
n/5< (n+0.5)/10

n=40
n5>(n+0.5)/10

Insufficient.

Thus, A.

OA?

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by kris610 » Fri Oct 03, 2008 4:30 pm
The question essentially asks:

0.2n > 0.1n+0.05 or 0.2n < 0.1n+0.05.

For the first n>0.5 and for the latter n<0.5.

A tells you n<0.1 so this is sufficient to tell you 0.2n>0.1n+0.05.

B is not sufficient as n may or may not be > 0.5.

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by 4meonly » Sun Oct 05, 2008 4:13 am
kris610 wrote:The question essentially asks:

0.2n > 0.1n+0.05 or 0.2n < 0.1n+0.05.

For the first n>0.5 and for the latter n<0.5.

A tells you n<0.1 so this is sufficient to tell you 0.2n>0.1n+0.05.

B is not sufficient as n may or may not be > 0.5.
4me question asks
0.2n > 0.1(n+0.5)
0.2n > 0.1n+0.05
n>0,5?

Only (1) gives the answer n<0,1 then it is not more than 0,5

A