PSLE Japheth saved a total of $66 in coins in his coin box.
25 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 fifty-cent coins. How many coins did Japheth save in his coin box altogether?
|
One-dollar |
Ten-cent |
Fifty-cent |
Total |
Comparison between the number of 3 types of coins |
2x2 4 u |
3x2 6 u |
5x2 10 u
|
Comparison between the number of one-dollar and ten-cent coins |
4x1 |
1x1 |
|
|
Number |
4 u |
1 u |
5 u |
10 u |
Value |
1 |
0.1 |
0.5 |
|
Number x value |
4 u |
0.1 u |
2.5 u |
6.6 u |
Number of $1 coins is the repeated identity.
Make the number of $1 coins the same.
LCM of 2 and 4 = 4
Total value of coins = 6.6 u
6.6 u = 66
1 u = 66 ÷ 6.6 = 10
Total number of coins
= 4 u + 1 u + 5 u
= 10 u
= 10 x 10
= 100
Answer(s): 100