In a class of 100 students there are 70 boys whose average marks in a subject are 75. If the average marks of the complete class is 72, then what is the average of the girls ?

In a class of 100 students, there are 70 boys whose average marks in a subject is 75. If the average marks of the complete class is 72, then what is the average of the girls ?

In a class of 40 students, 45% are girls and the remaining are boys. If the average of the girls marks is 54 and that of the boys is 46, what is the average of the whole class?

In a class of 10 boys and 15 girls, the average score on a biology test is 90. If the average score for the girls is x, what is the average score for the boys in terms of x ?

In a class, 10% of the girls have eyes, and 20% of the boys have blue eyes. If the ratio of girls to boys in the class is 3 : 4, then what is the fraction of the fraction of the students in the class having blue eyes?

In a class of 40 students, 45% are girls. Find the number of boys in the class .

Out of 25 students of a class, 16 are girls. What is the percentage of girls?

The average of r and s is 7.5, and the average of r, s and t is 11. What is the value of t?

In a class of 36 students, 20 are girls and the rest are boys. Find the ratio of: the number of girls to the number of boys.

In a class of 50 students, 20 are boys and rest are girls. A student is selected at random. Find the probability of selecting a boy.

In a class of 75 students, 15 are above average, 45 are average and the rest below average achievers. The probability that an above average achieving student fails is 0.005, that an average achieving student fails is 0.05 and the probability of a below average achieving student failing is 0.15. If a student is known to have passed, what is the probability that he is a below average achiever?