Question

im confused, my question is how do you work out this question:

What do you add to 2 1/7 to make 4?

Answer 1

Let the no. be x

21/7 +x  = 4

x = 4-21/7

x = 28/7-21/7

x = 4/7

Answer 2

I would be on because 27/7 equals 21 divided by seven and that is 3.
so 4-3 equals 1