Bunuel wrote:

A certain road trip was completed in two parts interrupted by an hour-long lunch break. During the first portion of the trip the average speed was 55 miles per hour and the average speed during the second part of the trip was 63 miles per hour. If the trip was 480 miles long and took a total of 9 hours then which of the following is the amount of time spent driving before the lunch break?

A. 2

B. 3

C. 4

D. 5

E. 6

Guys, I got an interesting solution, I solved it in under 30 seconds. Just by looking at the speeds and the total distance.

Given Speed 1 = 55 mph & Speed 2 = 63 mph

The options given are all whole numbers, so 55*x + 63*y = 480 miles. We need to find "x"

In order for x to be whole number, y can be only 5 because its the only number between 1 and 9 which gives possible multiple of 55.

So then if y=5, then x=9-5-1=3

So, B is the answer in 30 sec