There are some pink and silver beads in a box. If 3 pink beads are removed from the box, the total number of beads left will be 9 times the number of pink beads left. If 36 silver beads are removed from the box, the total number of beads left will be 3 times the number of pink beads. How many beads are there in the box?
|
Case 1 |
Case 2 |
|
Pink beads |
Silver beads |
Pink beads |
Silver beads |
Before |
1 u + 3 |
8 u |
1 p |
2 p + 36 |
Change |
- 3 |
|
|
- 36 |
After |
1 u |
8 u |
1 p |
2 p |
Number of silver beads in the end for Case 1
= 9 u - 1 u
= 8 u
Number of pink beads in the end for Case 2
= 3 p - 1 p
= 2 p
The number of pink 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 + 3 = 1 p --- (1)
8 u = 2 p + 36
8 u - 36 =
2 p --- (2)
Make p the same.
(1)
x2 2 u + 6 =
2 p --- (3)
(2) = (3)
8 u - 36 = 2 u + 6
8 u - 2 u = 6 + 36
6 u = 42
1 u = 42 ÷ 6 = 7
Number of beads in the box
= (1 u + 3) + 8 u
= 9 u + 3
= (9 x 7) + 3
= 63 + 3
= 66
Answer(s): 66