Quant Problem

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Quant Problem

by sukh » Tue Oct 25, 2011 7:55 am
If the power of an engine grows by 10% when the number of its cylinders is increased by one, which of the following is closest to the ratio of the power of a 9-cylinder engine to that of a 12-cylinder engine? (A) 0.69 (B) 0.71 (C) 0.72 (D) 0.75 (E) 0.78

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by suyashgupta0562 » Tue Oct 25, 2011 2:39 pm
Time taken - 57 Seconds
IMO - D

Let the power of the 9 cylinder be 100
10 cylinder - 110
11 - Cylinder - 121
12 cylinder - 133

Ratio -100/133

Comes to approx 0.75.

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by VivianKerr » Thu Oct 27, 2011 8:01 pm
Let's say a 9 cylinder engine has a power of 100

A 10 cylinder would be 110

An 11 cylinder would be 1.1 x 110 = 121

A 12 cylinder would be 1.1 x 121 = 133.1

The ratio is 100/133.1 = approx .75.

IMO: D.
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