PSLE Ken had a total of 60 coins in his coin box.
23 of all the coins saved were one-dollar coins. There were 4 times as many one-dollar coins as ten-cent coins. The remaining coins were twenty-cent coins. What was the total value of all the coins in his coin box?
|
One-dollar |
Ten-cent |
Twenty-cent |
Total |
Comparison between the number of 3 types of coins |
2x2 4 u |
1x2 2 u |
3x2 6 u
|
Comparison between the number of one-dollar and ten-cent coins |
4x1 |
1x1 |
|
|
Number |
4 u |
1 u |
1 u |
6 u |
Value |
1 |
0.1 |
0.2 |
|
Number x value |
4 u |
0.1 u |
0.2 u |
4.3 u |
Number of $1 coins is the repeated identity.
Make the number of $1 coins the same.
LCM of 2 and 4 = 4
Total number of coins = 6 u
6 u = 60
1 u = 60 ÷ 6 = 10
Total value of coins
= 4 u 0.1 u 0.2 u
= 4.3 u
= 4.3 x 10
= $43
Answer(s): $43