Question

Use a common denominator write an equivalent fraction for each fraction

Answer 1

The common denominator would be 40.
You need to multiply 2 by 8, and 5 by 8 to get 16/40.
Then you need to multiply 1 by 5, and 8 by 5 to get 5/40.
The final answers are 2/5 = 16/40 and 1/8 = 5/40.

Answer 2

The common denominator of 5 and 8 is forty. 
To go about solving this, do this:
2/5 and 1/8
2*8/5*8 and 1*5/8*5
16/40 and 5/40
Hope this helps!! :)