B
First you have to change 2 1/2 into 5/2
To multiply fractions use the method
Keep Change Flip
5/2 x 3/1 =15/2
Which simplifies to 7 1/2
The <em><u>correct answer</u></em> is:
624 crayons.
Explanation:
In 12 of the boxes, 28 crayons have not been used; this leaves 64-28=36 crayons that have been used. 12(36) = 432 crayons have been used in these boxes.
3 full boxes have been used; this is 3(64) = 192 crayons.
Together this makes 432+192 = 624 crayons that have been used.
