Hi,

Can someone help explain the reasoning behind the answer to this question?

## The Quasi JX - Mba.com IR Practice

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Pick some easy numbers. Say S = 90, so we're covering 90km/hour. And we'll say that E = 30, so we're going 30 km/1 liter. (Which is the same as saying that 1 liter allows us to cover 30km.)

If we drive for one hour at 90km/hour, we'll cover exactly 90km. If we cover 90km, and 1 liter allows us to cover 30km, we'll use a total of 3 liters. Now check to see which expression gives us a value of 3. S/E = 90/30 = 3. Check [spoiler]S/E[/spoiler] on the left

If we cover 60 km, and 1 liter allows us to cover 30km, we'll use 2 liters. 60/E = 60/30 = 2. Check [spoiler]60/E[/spoiler] on the right.