Problema Solution

It takes Company A 20 hours to upgrade a home heat pump. It takes 12 hours if Company A and company B work together? How long would it take Company B alone to install the heat pump?

Answer provided by our tutors

Let 'b' represent the hours that Company B need to install the heat pump alone.

Company A's rate is: 1/20 pumps per hour

Company B's rate is: 1/b pumps per hour

Together rate is: 1/12 pumps per hour

Now we can write:

1/30 + 1/b = 1/12

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click here to see the equation solved for b

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b = 30 hr

When working alone, Company B will install the heat pump in 30 hours.