Iraq and Brazil took part in Youth Games. From Iraq, the ratio of the number of male supporters to the number of female supporters was 4 : 7. From Brazil, the ratio of the number of male supporters to the number of female supporters was 3 : 5. The total number of supporters from Iraq was ¹¹₂₄ the total number of supporters from Brazil.

1. What was the ratio of the number of male supporters from Iraq to the total number of male supporters from both countries? Express the answer in the simplest form.
2. After 320 male supporters from both countries left the games, the percentage of all the female supporters became 88%. How many more female supporters from Brazil than Iraq were there at first?

Iraq		Brazil
11 u		24 u
Male supporters	Female supporters	Male supporters	Female supporters
4	7	3x3	5x3
4 u	7 u	9 u	15 u

(a)
Number of male supporters from Brazil
= ³₈ x 24 u
= 9 u

Number of female supporters from Iraq
= ⁵₈ x 24 u
= 15 u

Total number of male supporters
= 4 u + 9 u
= 13 u

Male supporters from Iraq : Total male supporters
4 : 13

(b)

	Male supporters	Female supporters
Before	13x4 = 52%	22x4 = 88%
Change	- 320
After	12%	88%

Number of male supporters in the end in percent
= 100% - 88%
= 12%

Total number of female supporters at first
= 7 u + 15 u
= 22 u

After 320 male supporters from both countries left the games, the percentage of all the female supporters became 88%.

Since only male supporters left the games, the number of female supporters remains unchanged. Make the number of female supporters the same.

22 u = 88%

1 u = 88% ÷ 22 = 4%

Number of male supporters at first in percent
= 13 x 4%
= 52%

Number of male supporters from both countries who left
= 52% - 12%
= 40%

40% = 320 

1% = 320 ÷ 40 = 8

Number of more female supporters from Brazil than Iraq at first
= 15 u - 7 u
= 8 u
= 8 x 4%
= 32%
= 32 x 8
= 256 

Answer(s): (a) 4 : 13; (b) 256