There was an equal number of green and white marbles in a bag at first. After 20 white marbles were taken out and 25 green marbles were added into the bag, there was
16 as many white marbles as green marbles. Find the number of white marbles in the bag at first.
|
Green marbles |
White marbles |
Before |
6 u - 25 |
1 u + 20 |
Change |
+ 25 |
- 20 |
After |
6 u |
1 u |
The number of green and white marbles in the bag is the same at first.
6 u - 25 = 1 u + 20
6 u - 1 u = 20 + 25
5 u = 45
1 u = 45 ÷ 5 = 9
Number of white marbles at first
= 1 u + 20
= 9 + 20
= 29
Answer(s)29