There was an equal number of white and green marbles in a box at first. After 22 green marbles were taken out and 20 white marbles were added into the box, there was
17 as many green marbles as white marbles. Find the number of green marbles in the box at first.
|
White marbles |
Green marbles |
Before |
7 u - 20 |
1 u + 22 |
Change |
+ 20 |
- 22 |
After |
7 u |
1 u |
The number of white and green marbles in the box is the same at first.
7 u - 20 = 1 u + 22
7 u - 1 u = 22 + 20
6 u = 42
1 u = 42 ÷ 6 = 7
Number of green marbles at first
= 1 u + 22
= 7 + 22
= 29
Answer(s)29