Teamwork

Algebra Level pending

It takes Michael 50 minutes to mow the lawn. Both Billy and Arielle can do it each alone in 25 minutes. Assuming the all have lawnmowers and they don't get in each other's way, how long will it take all of them working together to mow the lawn?


The answer is 10.

Elad Lending by Elad Lending , 65, Israel

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

2 solutions

It takes Michael 1 minute to mow 1/50th of the lawn. Likewise, it takes both Billy and Arielle 1 minute to mow 1/25th of the lawn. Together, in 1 minute, they can mow 1/50+1/25+1/25 of the lawn or 1/10th. Hence, to mow 10/10th of the lawn together, it will take them (10/10 * 1 minute)/(1/10) = 10/10 * 1 * 10=10 minutes!

0 Helpful 0 Interesting 0 Brilliant 0 Confused
Fd Móòn
Mar 7, 2016

If all of them work together, it would take
1 1 50 + 1 25 + 1 25 \frac {1}{\frac {1}{50} + \frac {1}{25} + \frac {1}{25}} minutes = 1 1 + 2 + 2 50 \frac {1}{\frac {1+2+2}{50} } minutes = 50 5 \frac{50}{5} minutes = 10 minutes.

0 Helpful 0 Interesting 0 Brilliant 0 Confused

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...