Task performed by one computer in 3 hrs = 15

to perform 80 tasks computers required are 80/15 = 5.33

as the computers cannot be in fraction so answer should be 6

\(\frac{30 tasks}{6 hours} = \frac{5 tasks}{1 hour}\)

Let x = # of machines
So, if we multiply the # of machines by the rate per machine and set that equal to 80/3 we should be able to solve

\(x(\frac{5 tasks}{hour})= \frac{80 tasks}{3 hours}\)

solve for x

\(x = \frac{80 tasks}{3 hours}*\frac{1 hour}{5 tasks}\)

\(x = \frac{80}{15} = 5\frac{5}{15} = 5\frac{1}{3}\)

So, we need at least 5 and 1/3 machines, and since machines don't come in less than whole numbers, we need 6 machines.

PS I mean "computers" not "machines"

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