Question

Sam made ten to add 7 + 2 + 6 Enter number to complete the equation. Sam first added 7 + 2 = 9. Then he made 10 to find the find the sum. The sum is 4 + 6 = 10 + ? = ?

Answer 1

So we have the addition.

7 + 2 + 6.

First, she added the 7 + 2 = 9

So we can replace that in our addition as:

7 + 2 + 6 = (7 + 2) + 6 = 9 + 6

Now, we can use 9 = 5 + 4, and replace that in the addition.

Then we have:

9 + 6 = (5 + 4) + 6

And we know that 4 + 6 = 10.

Then:

5 + 4 + 6 = 5 + (4 + 6) = 5 + 10 = 15.