In a shop, the number of cartons of pear juice sold was
12 the number of cartons left. When 75 more cartons were sold, the total number of cartons sold was 10 less than
47 the number of cartons the shop had at first. How many cartons were left?
|
Sold |
Left |
Total |
Before |
1x7 = 7 u |
2x7 = 14 u |
3x7 = 21 u
|
Change |
+ 75 |
- 75 |
|
After |
7 u + 75 |
14 u - 75 |
21 u |
Comparing the total number of cartons sold and the total number of cartons at first |
4x3 - 10 = 12 u - 10 |
|
7x3 = 21 u |
The total number of cartons is repeated. Make the total number of cartons the same. LCM of 3 and 7 is 21.
The number of cartons sold in the end is repeated.
12 u - 10 = 7 u + 75
12 u - 7 u = 75 + 10
5 u = 85
1 u = 85 ÷ 5 = 17
Number of cartons left
= 14 u - 75
= 14 x 17 - 75
= 238 - 75
= 163
Answer(s): 163