The following bar graph shows the percentage of students from five different colleges who are selected for a maths quiz.

The ratio of the number of students in colleges P, Q, R, S and T is 2 : 4 : 3 : 1 : 3, respectively. If 25 students are selected from college P, then what is the total number of students selected for the quiz?

If 25 students are selected from college P.

number of students selected from college P = 5% = 25

1% = 5

total number of students in college P = 100% = 500

The ratio of the number of students in colleges P, Q, R, S and T is 2 : 4 : 3 : 1 : 3, respectively.

total number of students in college Q = $$\frac{500}{2}\times4$$ = 1000

total number of students in college R = $$\frac{500}{2}\times3$$ = 750

total number of students in college S = $$\frac{500}{2}\times1$$ = 250

total number of students in college T = $$\frac{500}{2}\times3$$ = 750

Total number of students selected for the quiz = number of students selected from college P + number of students selected from college Q + number of students selected from college R + number of students selected from college S + number of students selected from college T

= 25+1000 of 6%+750 of 10%+250 of 8%+750 of 8%

= $$25+1000\times\frac{6}{100}+750\times\frac{10}{100}+250\times\frac{8}{100}+750\times\frac{8}{100}$$

= 25+60+75+20+60

= 240