Mrs Hun had a total of 165 white and pink roses in the ratio of 8 : 3. After she had given away 5 times as many white roses as pink roses, the number of white and pink roses left was in the ratio of 3 : 2. How many more white roses than pink roses did she give away?
|
White |
Pink |
Total |
Before |
8 b |
3 b |
11 b |
Change |
- 5 u |
- 1 u |
|
After |
3 p |
2 p |
|
|
Make p the same (1)x2 = (3) |
White (1) |
Pink (2) |
Make p the same (2)x3 = (4) |
Before |
240 |
120 |
45 |
135 |
Change |
- 10 u |
- 5 u |
- 1 u |
- 3 u |
After |
6 p |
3 p |
2 p |
6 p |
Number of roses at first
= 8 b + 3 b
= 11 b
11 b = 165
1 b = 165 ÷ 11 = 15
Number of white roses at first
= 8 b
= 8 x 15
= 120
Number of pink roses at first
= 3 b
= 3 x 15
= 45
120 - 5 u = 3 p --- (1)
45 - 1 u = 2 p --- (2)
Make p the same.
(1)
x2 240 - 10 u =
6 p --- (3)
(2)
x3 = (4)
135 - 3 u =
6 p --- (4)
(3) = (4)
240 - 10 u = 135 - 3 u
10 u - 3 u = 240 - 135
7 u = 105
1 u = 105 ÷ 7 = 15
Number of more white roses than pink roses that she gave away
= 5 u - 1 u
= 4 u
= 4 x 15
= 60
Answer(s): 60