Risa bought some stamps. She gave
16 of the stamps to her sister and sold
34 of the remaining stamps. After that, she bought another 228 stamps and had the same number of stamps that she bought at first. How many stamps did Risa buy at first?
| Her sister |
Remaining stamps |
Bought stamps |
Total |
1x4 =
4 u |
5x4 =
20 u |
|
6x4 =
24 u |
| |
Sold |
Left |
|
|
| |
3x5 |
1x5 |
|
|
| 4 u |
15 u |
5 u |
228 |
|
The remaining number of stamps before Risa bought another 228 stamps is repeated. Make the remaining number of stamps the same. LCM of 5 and 4 is 20.
Total number of stamps at first = 24 u
Number of stamps that Risa had left and bought after that = 5 u + 228
24 u = 5 u + 228
24 u - 5 u = 228
19 u = 228
1 u = 228 ÷ 19 = 12
Total number of stamps at first
= 24 u
= 24 x 12
= 288
Answer(s): 288
