There was an equal number of red and blue beads in a bag at first. After 30 blue beads were taken out and 42 red beads were added into the bag, there was
17 as many blue beads as red beads. Find the number of blue beads in the bag at first.
| |
Red beads |
Blue beads |
| Before |
7 u - 42 |
1 u + 30 |
| Change |
+ 42 |
- 30 |
| After |
7 u |
1 u |
The number of red and blue beads in the bag is the same at first.
7 u - 42 = 1 u + 30
7 u - 1 u = 30 + 42
6 u = 72
1 u = 72 ÷ 6 = 12
Number of blue beads at first
= 1 u + 30
= 12 + 30
= 42
Answer(s)42
