PSLE Albert saved a total of $125 in coins in his coin box.
59 of all the coins saved were one-dollar coins. There were 2 times as many one-dollar coins as twenty-cent coins. The remaining coins were fifty-cent coins. How many coins did Albert save in his coin box altogether?
|
One-dollar |
Twenty-cent |
Fifty-cent |
Total |
Comparison between the number of 3 types of coins |
5x2 10 u |
4x2 8 u |
9x2 18 u
|
Comparison between the number of one-dollar and twenty-cent coins |
2x5 |
1x5 |
|
|
Number |
10 u |
5 u |
3 u |
18 u |
Value |
1 |
0.2 |
0.5 |
|
Number x value |
10 u |
1 u |
1.5 u |
12.5 u |
Number of $1 coins is the repeated identity.
Make the number of $1 coins the same.
LCM of 5 and 2 = 10
Total value of coins = 12.5 u
12.5 u = 125
1 u = 125 ÷ 12.5 = 10
Total number of coins
= 10 u + 5 u + 3 u
= 18 u
= 18 x 10
= 180
Answer(s): 180