Math
posted by Mazhar
In a class, 2/7 of the pupils are girls. 1/2 of the girls and 1/3 of the boys in the class wear glasses. If 10 boys wear glasses, how many of the girls wear glasses?

Reiny
total number of students  x
number of girls = (2/7)x
number of boys = (5/7)x
number of girls with glasses = (1/2)(2/7)x = (1/7)x
number of boys with glasses = (1/3)(5/7)x = (5/21)x
given: (5/21)x = 10
solve for x, and sub into my definition
Respond to this Question
Similar Questions

Math
A class is made up of 10 boys and 2 girls. Half of the boys wear glasses. A student is selected at random from the class. What is the probability that the student is a boy with glasses? 
Maths
There are 36 pupils in a class. Each girl is given 8 books and each boy is given 3 books. The total number of books the girls receive is 46 more than the total number of books the boys receive. How many girls are there in the class? 
math
In a certain high school class, consisting of 60 girls and 40 boys, it is observed that 24 girls and 16 boys wear eye glasses, if a student is picked at random from this class. What is the probability that student picked at random … 
maths
in a class there are 50 students,15 girls wear glasses 8 do not wear glasses.20 boys don't wear glasses.how many students wore glasses 
Maths
In a class of 39 pupils, 1/4 of the girls wear spectacles and 2/3 of the boys wear spectacles. A total of 16 pupils in the class wear spectacles. How many girls do not wear spectacles? 
Maths
Please help... The ratio of the number of boys to that of girls in Class A is 2 : 3. The ratio of the number of girls who wear glasses to the number of girls who do not wear glassesis 1:3. If there are 12 more girls than boys, how … 
mathematics
in a class of 60 boys and 40 girls, it is observed tha 24 boys and 21 girls wear glasses. what is the probability that: (1)A student is picked at random from this calss wear glasses (2)A girl picked at random does not wear glsses.(3)A … 
MATH
Out of 1200 pupils in a school, 900 are boys and the rest are girls. If 20% of the boys and 30% of the girls wear spectacles,find: a.how many pupils in wear spectacles b.what percent of the total number of pupils wear spectacles. 
Math
2/5 of the 40 students in class are girls. 1/4 of the girls wear glasses. How many girls do not wear glasses? 
Math
In a class of 20 students, 40% are boys. Twentyfive percent of the boys and 50% of the girls wear glasses. How many students wear glasses?