There are some green and silver beads in a container. If 10 green beads are removed from the container, the total number of beads left will be 5 times the number of green beads left. If 4 silver beads are removed from the container, the total number of beads left will be 3 times the number of green beads. How many beads are there in the container?
|
Case 1 |
Case 2 |
|
Green beads |
Silver beads |
Green beads |
Silver beads |
Before |
1 u + 10 |
4 u |
1 p |
2 p + 4 |
Change |
- 10 |
|
|
- 4 |
After |
1 u |
4 u |
1 p |
2 p |
Number of silver beads in the end for Case 1
= 5 u - 1 u
= 4 u
Number of green beads in the end for Case 2
= 3 p - 1 p
= 2 p
The number of green beads at first is the same for Case 1 and Case 2.
The number of silver beads at first is also the same for Case 1 and Case 2.
1 u + 10 = 1 p --- (1)
4 u = 2 p + 4
4 u - 4 =
2 p --- (2)
Make p the same.
(1)
x2 2 u + 20 =
2 p --- (3)
(2) = (3)
4 u - 4 = 2 u + 20
4 u - 2 u = 20 + 4
2 u = 24
1 u = 24 ÷ 2 = 12
Number of beads in the container
= (1 u + 10) + 4 u
= 5 u + 10
= (5 x 12) + 10
= 60 + 10
= 70
Answer(s): 70