PSLE Irene had an equal number of yellow and pink beads. She gave 21 yellow beads and 11 pink beads to Mary. She gave the remaining beads to Nora. Nora was given 3 yellow beads for every 5 pink beads. How many beads did Irene have at first?
|
Yellow |
Pink |
Before |
3 u + 21 |
5 u + 11 |
Change |
- 21 |
- 11 |
After |
3 u |
5 u |
The number of yellow and pink beads is equal at first.
3 u + 21 = 5 u + 11
5 u - 3 u = 21 - 11
2 u = 10
1 u = 10 ÷ 2 = 5
Number of yellow beads that Irene had at first
= 3 u + 21
= 3 x 5 + 21
= 15 + 21
= 36
Number of beads that Irene had at first
= 2 x 36
= 72
Answer(s): 72