Bag N contains 20-cent coins and Bag P contains 5-cent coins. There are 12 more coins in Bag P than in Bag N. The amount of money in Bag N is 90¢ more than the amount of money in Bag P. How many total coins are there?
|
Bag N |
Bag P |
Number |
1 u |
1 u + 12 |
Value |
20¢ |
5¢ |
Total value |
20 u |
5 u + 60 |
Total value of 20¢ coins in Bag N
= 20 x 1 u
= 20 u
Total value of 5¢ coins in Bag P
= 5 x (1 u + 12)
= 5 u + 60
The amount in Bag N is 90¢ more than Bag P. If another 90¢ is added into Bag P, both Bag N and Bag P will have the same amounts of money.
20 u = 5 u + 60 + 90
20 u - 5 u = 60 + 90
15 u = 150
1 u = 150 ÷ 15 = 10
Total number of coins
= 1 u + (1 u + 12)
= 2 u + 12
= 2 x 10 + 12
= 20 + 12
= 32
Answer(s): 32