PSLE Risa had an equal number of red and white beads. She gave 33 red beads and 12 white beads to Mary. She gave the remaining beads to Nora. Nora was given 5 red beads for every 8 white beads. How many beads did Risa have at first?
|
Red |
White |
Before |
5 u + 33 |
8 u + 12 |
Change |
- 33 |
- 12 |
After |
5 u |
8 u |
The number of red and white beads is equal at first.
5 u + 33 = 8 u + 12
8 u - 5 u = 33 - 12
3 u = 21
1 u = 21 ÷ 3 = 7
Number of red beads that Risa had at first
= 5 u + 33
= 5 x 7 + 33
= 35 + 33
= 68
Number of beads that Risa had at first
= 2 x 68
= 136
Answer(s): 136