Answer:

Step-by-step explanation:
Divide 5 by 2 representing each box by the price. Which equals to $2.50 each box.
Answer: it equals 20
Step-by-step explanation:
10 x 20 = 120, hoped this helped.
Answer:
a)15:6 b)2:3
Step-by-step explanation:
No. of used books=15-9=6
a) 15:6
b)
6:9
2:3