A drink stall had 150 small and big bottles of milk. The number of small bottles is
213 of the number of big bottles. After selling a few big bottles of milk, there are
15 as many small bottles as big bottles left. How many big bottles of milk were sold?
|
Small bottles |
Big bottles |
Total |
Before |
2 u |
13 u |
15 u |
Change |
|
- 3 u |
|
After |
1x2 = 2 u |
5x2 = 10 u |
|
The number of small bottles remains unchanged. Make the number of small bottles the same. LCM of 2 and 1 is 2.
Number of small bottles at first = 2 u
Number of big bottles at first = 13 u
Total number of bottles at first
= 2 u + 13 u
= 15 u
15 u = 150
1 u = 150 ÷ 15 = 10
Number of big bottles sold
= 13 u - 10 u
= 3 u
= 3 x 10
= 30
Answer(s): 30