There was an equal number of yellow and purple balls in a bag at first. After 15 purple balls were taken out and 37 yellow balls were added into the bag, there was
13 as many purple balls as yellow balls. Find the number of purple balls in the bag at first.
| |
Yellow balls |
Purple balls |
| Before |
3 u - 37 |
1 u + 15 |
| Change |
+ 37 |
- 15 |
| After |
3 u |
1 u |
The number of yellow and purple balls in the bag is the same at first.
3 u - 37 = 1 u + 15
3 u - 1 u = 15 + 37
2 u = 52
1 u = 52 ÷ 2 = 26
Number of purple balls at first
= 1 u + 15
= 26 + 15
= 41
Answer(s)41
