In a shop, the number of cartons of persimmon juice sold was
13 the number of cartons left. When 56 more cartons were sold, the total number of cartons sold was 9 less than
910 the number of cartons the shop had at first. How many cartons were there at first?
|
Sold |
Left |
Total |
Before |
1x5 = 5 u |
3x5 = 15 u |
4x5 = 20 u
|
Change |
+ 56 |
- 56 |
|
After |
5 u + 56 |
15 u - 56 |
20 u |
Comparing the total number of cartons sold and the total number of cartons at first |
9x2 - 9 = 18 u - 9 |
|
10x2 = 20 u |
The total number of cartons is repeated. Make the total number of cartons the same. LCM of 4 and 10 is 20.
The number of cartons sold in the end is repeated.
18 u - 9 = 5 u + 56
18 u - 5 u = 56 + 9
13 u = 65
1 u = 65 ÷ 13 = 5
Number of cartons at first
= 20 u
= 20 x 5
= 100
Answer(s): 100