Coin Box M contains 50-cent coins and Coin Box N contains 10-cent coins. There are 27 more coins in Coin Box N than in Coin Box M. The amount of money in Coin Box M is 490¢ more than the amount of money in Coin Box N. How many total coins are there?
| |
Coin Box M |
Coin Box N |
| Number |
1 u |
1 u + 27 |
| Value |
50¢ |
10¢ |
| Total value |
50 u |
10 u + 270 |
Total value of 50¢ coins in Coin Box M
= 50 x 1 u
= 50 u
Total value of 10¢ coins in Coin Box N
= 10 x (1 u + 27)
= 10 u + 270
The amount in Coin Box M is 490¢ more than Coin Box N. If another 490¢ is added into Coin Box N, both Coin Box M and Coin Box N will have the same amounts of money.
50 u = 10 u + 270 + 490
50 u - 10 u = 270 + 490
40 u = 760
1 u = 760 ÷ 40 = 19
Total number of coins
= 1 u + (1 u + 27)
= 2 u + 27
= 2 x 19 + 27
= 38 + 27
= 65
Answer(s): 65
