There are a total of 340 pieces of 5-cent coins, 20-cent coins and 50-cent coins in Ryan's coin box.
45 of these coins are 5-cent coins. The number of 50-cent coins is thrice the number of 20-cent coins.
- How many 50-cent coins are there?
- What is the total value of the 50-cent coins in Ryan's coin box?
(a)
Number of 5-cent coins
=
45 x 340
= 272
Number of 20-cent coins and 50-cent coins
= 340 - 272
= 68
Number of 20-cent coins = 1 u
Number of 50-cent coins = 3 u
Number of 20-cent coins
= 1 u + 3 u
= 4 u
4 u = 68
1 u = 68 ÷ 4 = 17
Number of 50-cent coins
= 3 u
= 3 x 17
= 51
(b)
100¢ = $1
Total value of the 50-cent coins in Ryan's coin box
= 51 x 50
= 2550¢
= $25.50
Answer(s): (a) 51; (b) $25.50