Nora had some purple beads and grey beads in 2 boxes. In Box E, the ratio of the number of purple beads to grey beads was 9 : 5. In Box F, the number of purple beads was 2 times the number of grey beads. Nora transferred
25 of the grey beads from Box E to Box F. The number of beads in Box E became 48 and the ratio of the number of purple beads to grey beads in Box F became 6 : 7.
- How many grey beads were transferred from Box E to Box F?
- What was the number of beads in Box F after the transfer?
|
Box E |
Box F |
|
Purple |
Grey |
Purple |
Grey |
Comparing purple beads and grey beads at first |
9 u |
5 u |
2x3 = 6 p |
1x3 = 3 p |
Before |
|
5 u |
|
|
Change |
|
- 2 u |
|
+ 2 u |
After |
|
3 u |
|
|
Comparing purple beads and grey beads in the end |
9 u |
3 u |
6 p |
7 p |
(a)
Total number of beads in the end for Box E
= 9 u + 3 u
= 12 u
12 u = 48
1 u = 48 ÷ 12 = 4
Number of grey beads that were transferred from Box E to Box F
= 2 u
= 2 x 4
= 8
(b)
The number of purple beads in Box F remains unchanged. Make the number of purple beads in Box F the same. LCM of 2 and 6 is 6.
Increase in the number of grey beads in Box F
= 7 p - 3 p
= 4 p
4 p = 2 u
4 p = 8
1 p = 8 ÷ 4 = 2
Number of beads in Box F in the end
= 6 p + 7 p
= 13 p
= 13 x 2
= 26
Answer(s): (a) 8; (b) 26