188k views
3 votes
The ratio of girls to boys in Mr. Smith's homeroom is 3:4. The ratio in Mr. Smith's homeroom to students in the whole 7th grade is 1:5. The ratio of students in 7th grade to students in the whole middle school is 2:7. If there are 12 girls in Mr. Smith's homeroom, how many students are in the whole middle school?

User Walrus
by
7.1k points

1 Answer

4 votes

3:4 = G:B

1:5 = Mr. Smith's class: 7th Grade

2:7= 7th: Middle school

12 girls = 3 units

1 unit = 12/3= 4

Boys = 4x4= 16

Whole class = 28 students

Class : Grade = 1:5 7 = number of units in Mr. Smith's class

28 = 1 unit

5 units= 28x5= 140 There are 140 kids in the grade

140 = 2 units

1 unit = 140/2= 70

70x7=490

There are 490 students in the whole grade



User Nishant Chauhan
by
8.8k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.