Jar M contains 20-cent coins and Jar N contains 5-cent coins. There are 16 more coins in Jar N than in Jar M. The amount of money in Jar M is 220¢ more than the amount of money in Jar N. How many total coins are there?
| |
Jar M |
Jar N |
| Number |
1 u |
1 u + 16 |
| Value |
20¢ |
5¢ |
| Total value |
20 u |
5 u + 80 |
Total value of 20¢ coins in Jar M
= 20 x 1 u
= 20 u
Total value of 5¢ coins in Jar N
= 5 x (1 u + 16)
= 5 u + 80
The amount in Jar M is 220¢ more than Jar N. If another 220¢ is added into Jar N, both Jar M and Jar N will have the same amounts of money.
20 u = 5 u + 80 + 220
20 u - 5 u = 80 + 220
15 u = 300
1 u = 300 ÷ 15 = 20
Total number of coins
= 1 u + (1 u + 16)
= 2 u + 16
= 2 x 20 + 16
= 40 + 16
= 56
Answer(s): 56
