Problem of the week

What I know

Manny Kerr  runs a company that specializes in grooming and caring for lawns

Manny has a push mower and powerful riding mower

At one location takes 5 hours with mower

Takes 70 minutes with powerful riding mower

After 90% was cut using the rest was cut with powerful riding mower

How many minutes did it take for Manny to cut the entire lawn

Solution

We need to find 90% of 70 

0.9 x 70 = 63 minutes for power riding mower to mow the 90% of the lawn 

Takes 5 hours with mower to mow entire lawn so into minutes is 5 x 60 = 300 

Takes 300 minutes for mower to mow entire lawn

We need to find 10% of mower 300 divided by 10 = 30

So add them 30 + 63 = 93

So it would altogether take 93 minutes to mow 90% with power mower and 10% with mower