Question

49 to make 77 + 48 easier to solve, lou decides to first add on from 77 to get to the next ten. 49 add on to get to 80. 77 + \boxed{} = 80

Explanation:

Step1: Find difference to 80

$80 - 77 = 3$

Step2: Verify the equation

$77 + 3 = 80$

Answer:

3