roygush wrote:

A car goes 12 kilometers on a liter of gas when driven at 80 kilometers per hour.

when the car is driven at 50 kilometers per hour, it only goes 75% as far per liter gas

how many liters of gas will it take to travel 135 kilometers driving at 50 kilometers per hour?

(a)3

(b)5

(c)9

(d)11

(e)15

its a medium percents question.

sorry i dont have the OA.

i have seen a few of those and cant nail the trick.

thanks in advance.

OA has to be E.. (KPMH - km per hr)

@80 KMPH 1 lt gives 12 KM

@50 KMPH 1 lt will give 9 KM (75% of the original)

so @50 KMPH to cover 135 KM how many liters we need?

(135 KM) * (1/ 9 lt / KM )= 15 liters (KM in the numerator and denominator gets canceled to give liters , which is what we want!)

silly me.

so obvious.