PSLE Shannon had an equal number of black and silver beads. She gave 29 black beads and 15 silver beads to Mary. She gave the remaining beads to Nora. Nora was given 5 black beads for every 7 silver beads. How many beads did Shannon have at first?
|
Black |
Silver |
Before |
5 u + 29 |
7 u + 15 |
Change |
- 29 |
- 15 |
After |
5 u |
7 u |
The number of black and silver beads is equal at first.
5 u + 29 = 7 u + 15
7 u - 5 u = 29 - 15
2 u = 14
1 u = 14 ÷ 2 = 7
Number of black beads that Shannon had at first
= 5 u + 29
= 5 x 7 + 29
= 35 + 29
= 64
Number of beads that Shannon had at first
= 2 x 64
= 128
Answer(s): 128