PSLE Min had an equal number of black and white beads. She gave 36 black beads and 28 white beads to Mary. She gave the remaining beads to Nora. Nora was given 5 black beads for every 7 white beads. How many beads did Min have at first?
|
Black |
White |
Before |
5 u + 36 |
7 u + 28 |
Change |
- 36 |
- 28 |
After |
5 u |
7 u |
The number of black and white beads is equal at first.
5 u + 36 = 7 u + 28
7 u - 5 u = 36 - 28
2 u = 8
1 u = 8 ÷ 2 = 4
Number of black beads that Min had at first
= 5 u + 36
= 5 x 4 + 36
= 20 + 36
= 56
Number of beads that Min had at first
= 2 x 56
= 112
Answer(s): 112