Question

A hot air balloon is at an elevation of 1,250 feet. Its elevation begins to change at a rate of -22.5 feet per minute. How many minutes will it take the balloon to descend to an elevation of 935 feet? Use the Distance Formula: d = rt

Answer 1

Let y represent the number of feet and x represent the number of minutes.  Convert 22 1/2 to decimal form: 22.5

 

y = -22.5x

 

Plug in -315 for y

 

-315 = -22.5x

 

divide both sides by -22.5

 

14 = x

 

It will take 14 minutes.