In a school, 0.9 of the boys and 0.1 of the girls take part in quizzes. There is an equal number of girls and boys who do not take part in quizzes. If 198 students do not take part in quizzes, how many more students take part in quizzes than those who do not take part in quizzes?

Boys		Girls
Take part	Do not take part	Take part	Do not take part
9x9	1x9	1	9
	1x9		1x9
81 u	9 u	1 u	9 u

0.9 = ⁹₁₀
Boys that take part : Boys that do not take part = 9 : 1

0.1 = ¹₁₀
Girls that take part : Girls that do not take part = 1 : 9

The number of girls who do not take part is repeated.  Make the number of girls who do not take part the same.  LCM of 1 and 9 is 9.

Number of students who do not take part in quizzes
= 9 u + 9 u
= 18 u

18 u = 198

1 u = 198 ÷ 18 = 11

Number of students who take part in quizzes
= 81 u + 1 u
= 82 u

Number of more students who take part in quizzes than those who do not take part in quizzes
= 82 u - 18 u
= 64 u
= 64 x 11
= 704

Answer(s): 704