Question

A new section of freeway will be 8 1/2 mi long. During the first month of construction, 2 7/10 mi were built. During the second month, 3 3/5 mi were built. How many more miles were left to build?

Answer 1

You need to get commone denominators of 10ths first.
1/2 = 5/10 and 3/5 = 6/10

Add up the the two parts that were built and subtract from 8 5/10

Can you do it from here or do you need more help?

Answer 2

2 7/10 + 3 6/10 = 5 13/10 = 6 3/10

8 5/10 - 6 3/10 = ?

Answer 3

2 1/5

Answer 4

Right.