Question

1) Working alone, Beth can tar a roof in 151

Answer 1

Answer:

A) 7.24 hours

Step-by-step explanation:

The together rate is the sum of each separate rate.

In this problem:

Beth's rate is 1/15(suppose there was a small typing mistake there, with 151 none of the options are correct).

Mike's rate is 1/14

The together rate is 1/x

Then

We want to find x.

$\frac{1}{15} + \frac{1}{14} = \frac{1}{x}$

15*14 = 210. So

$\frac{14 + 15}{210} = \frac{1}{x}$

$\frac{29}{210} = \frac{1}{x}$

Cross multiplication

$29x = 210$

$x = \frac{210}{29}$

$x = 7.24$

So the correct answer is:

A) 7.24 hours