Question

Ari has 10 boards that are 7.8ft long. What is the total length of all the boards Ari has

Answer 1

7.8 • 10 = 78. 78 is the total length

Answer 2

"10 boards that are 7.8ft long" can be interpreted as 10 * 7.8

When multiplying a number by 10, just move the decimal one point over.

7.8 * 10 = 78

Ari has 78 feet worth of boards.