I need help with my summer math packet..

Question

There's 21 students in a class. The ratio of boys to girls is 3 to 4. How many boys are there? How many girls are there?

Answer 1

9 guys and 12 girls

Answer 2

A ratio means that there is a proportion between those two numbers: boys and girls.

To do this, first disregard the total number of students in the class (21)

Let's assume that there are only 3 boys and 4 girls. That makes it seven people in general, right?

3   :    4     -------> 3+4 = 7

Let's set up a proportion of 7 to 21. you know that 7 goes into 21 three times, so...

3 : 4 = 7

? : ? =21

Just multiply everything in the original line by 3

so

9:12 = 21

there are 9 boys

and 12 girls

let me know if you want any more help :)

Answer 3

boys=3

girls=4

total 21

3x+4x=21

7x=21

x=3

3x=9

4x=12

9 boys and 12 girls

Answer 4

There are 9 boys and 12 girls.

Answer mine?

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Answer 5

there would by 9 boys and 12 girls