There are a total of 200 pieces of 5-cent coins, 10-cent coins and 20-cent coins in Julian's glass jar.
25 of these coins are 5-cent coins. The number of 20-cent coins is four times the number of 10-cent coins.
- How many 20-cent coins are there?
- What is the total value of the 20-cent coins in Julian's glass jar?
(a)
Number of 5-cent coins
=
25 x 200
= 80
Number of 10-cent coins and 20-cent coins
= 200 - 80
= 120
Number of 10-cent coins = 1 u
Number of 20-cent coins = 4 u
Number of 10-cent coins
= 1 u + 4 u
= 5 u
5 u = 120
1 u = 120 ÷ 5 = 24
Number of 20-cent coins
= 4 u
= 4 x 24
= 96
(b)
100¢ = $1
Total value of the 20-cent coins in Julian's glass jar
= 96 x 20
= 1920¢
= $19.20
Answer(s): (a) 96; (b) $19.20