Question

The small submarine is at –1,320 feet in relation to sea level. The submarine needs to be 180 feet below sea level in 60 minutes.
How far must the submarine travel?

Answer 1

Answer:

The first submarine needs to travel at a rate of [-180 – (-1,320)] ÷ 60 = 19 feet per minute.

The second submarine needs to travel at a rate of [-180 – (-1,440)] ÷ 60 = 21 feet per minute.

21 – 19 = 2, so the second submarine must travel 2 feet per minute faster than the first sub.