Question

Gavin has a board that is ten feet long. Gavin is using the board to saw off pieces of wood needed for a building project. First Gavin saws off 2/10 of the board. Next Gavin saws off 5/10 of the board. Last Gavin saws off 1/10 of the board Gavin says he has 2/10 the board left to use for another building project is Gavin correct?

Answer 1

Gavin is correct

Explanation:

Since the problem is using a denominator of 10, I will convert 1 (1 representing the full length of the board before being sawed) to a fraction over 10

1 = 10/10

Subtract everything Gavin sawed off from the board

10/10 - 2/10 - 5/10 - 1/10

Only subtract the numerators; the denominators will stay the same

8/10 - 5/10 - 1/10

3/10 - 1/10

2/10

Gavin says he has 2/10 of the board left to use

Since we concluded we still have 2/10, he is correct