There are a total of 150 pieces of 5-cent coins, 10-cent coins and 50-cent coins in Tom's coin box.
25 of these coins are 5-cent coins. The number of 50-cent coins is five times the number of 10-cent coins.
- How many 50-cent coins are there?
- What is the total value of the 50-cent coins in Tom's coin box?
(a)
Number of 5-cent coins
=
25 x 150
= 60
Number of 10-cent coins and 50-cent coins
= 150 - 60
= 90
Number of 10-cent coins = 1 u
Number of 50-cent coins = 5 u
Number of 10-cent coins
= 1 u + 5 u
= 6 u
6 u = 90
1 u = 90 ÷ 6 = 15
Number of 50-cent coins
= 5 u
= 5 x 15
= 75
(b)
100¢ = $1
Total value of the 50-cent coins in Tom's coin box
= 75 x 50
= 3750¢
= $37.50
Answer(s): (a) 75; (b) $37.50