In a shop, the number of cartons of persimmon juice sold was
13 the number of cartons left. When 57 more cartons were sold, the total number of cartons sold was 8 less than
78 the number of cartons the shop had at first. How many cartons were left?
| |
Sold |
Left |
Total |
| Before |
1x2 =
2 u |
3x2 =
6 u |
4x2 =
8 u
|
| Change |
+ 57 |
- 57 |
|
| After |
2 u + 57 |
6 u - 57 |
8 u |
Comparing the total
number of cartons
sold and the total number of cartons at first |
7x1 - 8 =
7 u - 8 |
|
8x1 =
8 u |
The total number of cartons is repeated. Make the total number of cartons the same. LCM of 4 and 8 is 8.
The number of cartons sold in the end is repeated.
7 u - 8 = 2 u + 57
7 u - 2 u = 57 + 8
5 u = 65
1 u = 65 ÷ 5 = 13
Number of cartons left
= 6 u - 57
= 6 x 13 - 57
= 78 - 57
= 21
Answer(s): 21
