Question

Jamie, John, and Jake are on the prom committee. They are responsible for blowing up the balloons for prom night. John can blowup a balloon every 15 seconds while it takes Jamie and Jake 20 seconds per balloon. If 1 out of 80 balloons are found to be defected after they are inflated, Identify the expression which represents the number of balloons inflated per hour.
A) 592.5x
B) 592.5 - 1/80x
C) 600x - 1/80
D) 600 - 1/80x

Answer 1

First, pass all the rate of inflation to ballons/hour

John: 1 b/15s * 3600 s/h = 240 b/h
Jamie: 1 b/20s * 3600 s/h = 180 b/h
Jake: 180 b/h

Then sum the rates to obtain the total rate

Total ballons per hour: 240 b/h + 180 b/h + 180b/h = 600 b/h

If it passes x hours the number of ballons inflated is 600*x

The number of ballon defective are 600*x/80

The number of ballons effectiveley inflated = 600x -600x/80 = 600x - 7.5x = 592.5x.

Answer: option A)