Pouch V contains 50-cent coins and Pouch W contains 20-cent coins. There are 21 more coins in Pouch W than in Pouch V. The amount of money in Pouch V is 390¢ more than the amount of money in Pouch W. How many total coins are there?
|
Pouch V |
Pouch W |
Number |
1 u |
1 u + 21 |
Value |
50¢ |
20¢ |
Total value |
50 u |
20 u + 420 |
Total value of 50¢ coins in Pouch V
= 50 x 1 u
= 50 u
Total value of 20¢ coins in Pouch W
= 20 x (1 u + 21)
= 20 u + 420
The amount in Pouch V is 390¢ more than Pouch W. If another 390¢ is added into Pouch W, both Pouch V and Pouch W will have the same amounts of money.
50 u = 20 u + 420 + 390
50 u - 20 u = 420 + 390
30 u = 810
1 u = 810 ÷ 30 = 27
Total number of coins
= 1 u + (1 u + 21)
= 2 u + 21
= 2 x 27 + 21
= 54 + 21
= 75
Answer(s): 75