PSLE Sarah had an equal number of grey and white beads. She gave 37 grey beads and 13 white beads to Mary. She gave the remaining beads to Nora. Nora was given 3 grey beads for every 5 white beads. How many beads did Sarah have at first?
|
Grey |
White |
Before |
3 u + 37 |
5 u + 13 |
Change |
- 37 |
- 13 |
After |
3 u |
5 u |
The number of grey and white beads is equal at first.
3 u + 37 = 5 u + 13
5 u - 3 u = 37 - 13
2 u = 24
1 u = 24 ÷ 2 = 12
Number of grey beads that Sarah had at first
= 3 u + 37
= 3 x 12 + 37
= 36 + 37
= 73
Number of beads that Sarah had at first
= 2 x 73
= 146
Answer(s): 146