In a shop, the number of cartons of peach juice sold was
12 the number of cartons left. When 15 more cartons were sold, the total number of cartons sold was 9 less than
56 the number of cartons the shop had at first. How many cartons were there at first?
|
Sold |
Left |
Total |
Before |
1x2 = 2 u |
2x2 = 4 u |
3x2 = 6 u
|
Change |
+ 15 |
- 15 |
|
After |
2 u + 15 |
4 u - 15 |
6 u |
Comparing the total number of cartons sold and the total number of cartons at first |
5x1 - 9 = 5 u - 9 |
|
6x1 = 6 u |
The total number of cartons is repeated. Make the total number of cartons the same. LCM of 3 and 6 is 6.
The number of cartons sold in the end is repeated.
5 u - 9 = 2 u + 15
5 u - 2 u = 15 + 9
3 u = 24
1 u = 24 ÷ 3 = 8
Number of cartons at first
= 6 u
= 6 x 8
= 48
Answer(s): 48