Coin Box L contains 20-cent coins and Coin Box M contains 5-cent coins. There are 25 more coins in Coin Box M than in Coin Box L. The amount of money in Coin Box L is 325¢ more than the amount of money in Coin Box M. How many total coins are there?
| |
Coin Box L |
Coin Box M |
| Number |
1 u |
1 u + 25 |
| Value |
20¢ |
5¢ |
| Total value |
20 u |
5 u + 125 |
Total value of 20¢ coins in Coin Box L
= 20 x 1 u
= 20 u
Total value of 5¢ coins in Coin Box M
= 5 x (1 u + 25)
= 5 u + 125
The amount in Coin Box L is 325¢ more than Coin Box M. If another 325¢ is added into Coin Box M, both Coin Box L and Coin Box M will have the same amounts of money.
20 u = 5 u + 125 + 325
20 u - 5 u = 125 + 325
15 u = 450
1 u = 450 ÷ 15 = 30
Total number of coins
= 1 u + (1 u + 25)
= 2 u + 25
= 2 x 30 + 25
= 60 + 25
= 85
Answer(s): 85
