Jar K contains 50-cent coins and Jar L contains 10-cent coins. There are 38 more coins in Jar L than in Jar K. The amount of money in Jar K is 300¢ more than the amount of money in Jar L. How many total coins are there?
| |
Jar K |
Jar L |
| Number |
1 u |
1 u + 38 |
| Value |
50¢ |
10¢ |
| Total value |
50 u |
10 u + 380 |
Total value of 50¢ coins in Jar K
= 50 x 1 u
= 50 u
Total value of 10¢ coins in Jar L
= 10 x (1 u + 38)
= 10 u + 380
The amount in Jar K is 300¢ more than Jar L. If another 300¢ is added into Jar L, both Jar K and Jar L will have the same amounts of money.
50 u = 10 u + 380 + 300
50 u - 10 u = 380 + 300
40 u = 680
1 u = 680 ÷ 40 = 17
Total number of coins
= 1 u + (1 u + 38)
= 2 u + 38
= 2 x 17 + 38
= 34 + 38
= 72
Answer(s): 72
