Question

Lisa can harvest a field in 9.3 hours. Kali can harvest

the same field in 9.7 hours. Find how long it would take
them if they worked together.

Answer 1

4.75 hours

Explanation:

First you need to find the median of the two numbers. The fastest way to do it is to add 9.3 and 9.7 and divide by 2, which will give you 9.5. Since there's going to be two of them working, divide 9.5 by 2, and you get 4.75.

Answer 2

1/9.3 + 1/9.7 = 1/x

x=4.74789

If simplicity is to be applied,

rounded to tens: 0

rounded to ones: 5

rounded to tenths:4.7

rounded to hundreths:4.75

rounded to thosandths:4.748