Question

Two construction elevators are starting at different heights on a building. The first is 130 feet high and is rising at a rate of 7 feet per minute. The second is 226 feet high and is descending at a rate of 5 feet per minute. How long will it take for them to be at the same height?

Answer 1

Answer: It will take 8 minutes to be on same height.

Explanation:

Let x= Time taken to be at same height.

The first is 130 feet high and is rising at a rate of 7 feet per minute.

Height = 130+7x

The second is 226 feet high and is descending at a rate of 5 feet per minute.

Height = 226-5x

According o the question,

`130+7x=226-5x\\\\\Rightarrow\ 7x+5x=226-130\\\\\Rightarrow\ 12x = 96\\\\\Rightarrow\ x=(96)/(12)\\\\\Rightarrow\ x=8`

Hence, it will take 8 minutes to be on same height.