There are some black and gold beads in a container. If 2 black beads are removed from the container, the total number of beads left will be 7 times the number of black beads left. If 32 gold beads are removed from the container, the total number of beads left will be 3 times the number of black beads. How many beads are there in the container?
|
Case 1 |
Case 2 |
|
Black beads |
Gold beads |
Black beads |
Gold beads |
Before |
1 u + 2 |
6 u |
1 p |
2 p + 32 |
Change |
- 2 |
|
|
- 32 |
After |
1 u |
6 u |
1 p |
2 p |
Number of gold beads in the end for Case 1
= 7 u - 1 u
= 6 u
Number of black beads in the end for Case 2
= 3 p - 1 p
= 2 p
The number of black beads at first is the same for Case 1 and Case 2.
The number of gold beads at first is also the same for Case 1 and Case 2.
1 u + 2 = 1 p --- (1)
6 u = 2 p + 32
6 u - 32 =
2 p --- (2)
Make p the same.
(1)
x2 2 u + 4 =
2 p --- (3)
(2) = (3)
6 u - 32 = 2 u + 4
6 u - 2 u = 4 + 32
4 u = 36
1 u = 36 ÷ 4 = 9
Number of beads in the container
= (1 u + 2) + 6 u
= 7 u + 2
= (7 x 9) + 2
= 63 + 2
= 65
Answer(s): 65