Iran and Brazil took part in Youth Games. From Iran, the ratio of the number of male supporters to the number of female supporters was 4 : 1. From Brazil, the ratio of the number of male supporters to the number of female supporters was 1 : 8. The total number of supporters from Iran was ⁵₂₇ the total number of supporters from Brazil.

1. What was the ratio of the number of male supporters from Iran to the total number of male supporters from both countries? Express the answer in the simplest form.
2. After another 28 male supporters from both countries joined the games, the percentage of all the female supporters became 75%. How many less female supporters from Iran than Brazil were there at first?

Iran		Brazil
5 u		27 u
Male supporters	Female supporters	Male supporters	Female supporters
4	1	1x3	8x3
4 u	1 u	3 u	24 u

(a)
Number of male supporters from Brazil
= ¹₉ x 27 u
= 3 u

Number of female supporters from Iran
= ⁸₉ x 27 u
= 24 u

Total number of male supporters
= 4 u + 3 u
= 7 u

Male supporters from Iran : Total male supporters
4 : 7

(b)

	Male supporters	Female supporters
Before	7x3 = 21%	25x3 = 75%
Change	+ 28
After	25%	75%

Number of male supporters in the end in percent
= 100% - 75%
= 25%

Total number of female supporters at first
= 1 u + 24 u
= 25 u

After another 28 male supporters from both countries joined the games, the percentage of all the female supporters became 75%.

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

25 u = 75%

1 u = 75% ÷ 25 = 3%

Number of male supporters at first in percent
= 7 x 3%
= 21%

Number of male supporters from both countries who joined the games
= 25% - 21%
= 4%

4% = 28 

1% = 28 ÷ 4 = 7

Number of less female supporters from Iran than Brazil at first
= 24 u - 1 u
= 23 u
= 23 x 3%
= 69%
= 69 x 7
= 483 

Answer(s): (a) 4 : 7; (b) 483