Bag A contains 20-cent coins and Bag B contains 10-cent coins. There are 15 more coins in Bag B than in Bag A. The amount of money in Bag A is 100¢ more than the amount of money in Bag B. How many total coins are there?
| |
Bag A |
Bag B |
| Number |
1 u |
1 u + 15 |
| Value |
20¢ |
10¢ |
| Total value |
20 u |
10 u + 150 |
Total value of 20¢ coins in Bag A
= 20 x 1 u
= 20 u
Total value of 10¢ coins in Bag B
= 10 x (1 u + 15)
= 10 u + 150
The amount in Bag A is 100¢ more than Bag B. If another 100¢ is added into Bag B, both Bag A and Bag B will have the same amounts of money.
20 u = 10 u + 150 + 100
20 u - 10 u = 150 + 100
10 u = 250
1 u = 250 ÷ 10 = 25
Total number of coins
= 1 u + (1 u + 15)
= 2 u + 15
= 2 x 25 + 15
= 50 + 15
= 65
Answer(s): 65
