PSLE Justin saved a total of $44 in coins in his coin box.
19 of all the coins saved were one-dollar coins. There were 3 times as many one-dollar coins as twenty-cent coins. The remaining coins were ten-cent coins. How many coins did Justin save in his coin box altogether?
|
One-dollar |
Twenty-cent |
Ten-cent |
Total |
Comparison between the number of 3 types of coins |
1x3 3 u |
8x3 24 u |
9x3 27 u
|
Comparison between the number of one-dollar and twenty-cent coins |
3x1 |
1x1 |
|
|
Number |
3 u |
1 u |
23 u |
27 u |
Value |
1 |
0.2 |
0.1 |
|
Number x value |
3 u |
0.2 u |
2.3 u |
5.5 u |
Number of $1 coins is the repeated identity.
Make the number of $1 coins the same.
LCM of 1 and 3 = 3
Total value of coins = 5.5 u
5.5 u = 44
1 u = 44 ÷ 5.5 = 8
Total number of coins
= 3 u + 1 u + 23 u
= 27 u
= 27 x 8
= 216
Answer(s): 216