Madeline has 5 boxes with 24 crayons in each. She noticed that 5/8 of the crayons in the 2 boxes were not yet used. In the 2 other boxes, only 2/3 of the crayons were used while the last box was not entirely used. How many unused crayons did Madeline have?
Thoughts? Step-by-step reasoning:
Two boxes of crayons have 24 x 5 / 8 = 15 unused crayons from each box. So, a total of 15 x 2 = 30 unused crayons are in the two boxes. For the other 2 boxes, there are 24 x 2 / 3 = 16 used crayons from each box. Hence, there are 24 - 16 = 8 unused crayons. So, a total of 8 x 2 = 16 unused crayons are in the other two boxes. Therefore, Madeline has a total of 30 + 16 + 24 = 70 unused crayons.
Thus, the answer is 70.