Mrs Ma had a total of 88 pink and white daisies in the ratio of 9 : 2. After she had given away 5 times as many pink daisies as white daisies, the number of pink and white daisies left was in the ratio of 7 : 3. How many more pink daisies than white daisies did she give away?

	Pink	White	Total
Before	9 b	2 b	11 b
Change	- 5 u	- 1 u
After	7 p	3 p

	Make p the same (1)x3 = (3)	Pink (1)	White (2)	Make p the same (2)x7 = (4)
Before	216	72	16	112
Change	- 15 u	- 5 u	- 1 u	- 7 u
After	21 p	7 p	3 p	21 p

Number of daisies at first
= 9 b + 2 b
= 11 b

11 b = 88

1 b = 88 ÷ 11 = 8

Number of pink daisies at first
= 9 b
= 9 x 8
= 72

Number of white daisies at first
= 2 b
= 2 x 8
= 16

72 - 5 u = 7 p --- (1)

16 - 1 u = 3 p --- (2)

Make p the same.

(1)_x3 
216 - 15 u = 21 p --- (3)

(2)_x7 = (4)
112 - 7 u = 21 p --- (4)

(3) = (4)
216 - 15 u = 112 - 7 u
15 u - 7 u = 216 - 112
8 u = 104

1 u = 104 ÷ 8 = 13

Number of more pink daisies than white daisies that she gave away
= 5 u - 1 u
= 4 u
= 4 x 13
= 52

Answer(s): 52