In a shop, the number of cartons of dragonfruit juice sold was
13 the number of cartons left. When 77 more cartons were sold, the total number of cartons sold was 4 less than
710 the number of cartons the shop had at first. How many cartons were left?
|
Sold |
Left |
Total |
Before |
1x5 = 5 u |
3x5 = 15 u |
4x5 = 20 u
|
Change |
+ 77 |
- 77 |
|
After |
5 u + 77 |
15 u - 77 |
20 u |
Comparing the total number of cartons sold and the total number of cartons at first |
7x2 - 4 = 14 u - 4 |
|
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.
14 u - 4 = 5 u + 77
14 u - 5 u = 77 + 4
9 u = 81
1 u = 81 ÷ 9 = 9
Number of cartons left
= 15 u - 77
= 15 x 9 - 77
= 135 - 77
= 58
Answer(s): 58