Bob mows a lawn in 45 minutes. Together Bob and Tom mow the lawn in 35 minutes. How long does it take Tom to mow the lawn by himself.

Question

Bob mows a lawn in 45 minutes. Together Bob and Tom mow the lawn in 35 minutes. How long does it take Tom to mow the lawn by himself.

Answer 1

35(1/45 + 1/x)= 1

 

35/45 + 35/x = 1

 

7/9 + 35/x = 1

 

1- 7/9 = 35/x

 

2/9 = 35/x

 

  (2/9)x = 35

 

x = 157.5 min