There was an equal number of black and pink balls in a bag at first. After 30 pink balls were taken out and 30 black balls were added into the bag, there was
15 as many pink balls as black balls. Find the number of pink balls in the bag at first.
|
Black balls |
Pink balls |
Before |
5 u - 30 |
1 u + 30 |
Change |
+ 30 |
- 30 |
After |
5 u |
1 u |
The number of black and pink balls in the bag is the same at first.
5 u - 30 = 1 u + 30
5 u - 1 u = 30 + 30
4 u = 60
1 u = 60 ÷ 4 = 15
Number of pink balls at first
= 1 u + 30
= 15 + 30
= 45
Answer(s)45