Answer:
60 boys
Step-by-step explanation:
boys : girls = 3 : 5
Total number of people = 160
Let y = common factor:
Therefore, 3y + 5y = 160
⇒ 8y = 160
⇒ y = 160 ÷ 8 = 20
Boys = 3y = 3 x 20 = 60
Girls = 5y = 5 x 20 = 100
So there are 60 boys and 100 girls
Answer:
3/8 = x/160
Step-by-step explanation:
First, you need to find the total amount of boys and girls, so you add 3+5.
3+5= 8
So 8 is the total, and out of 8 people, 3 of them are boys. Now that you have that, you can set up the first part of the proportion.
3/8
Now, what information does it give you about the people in the grade? It tells you the total amount, but not the number of boys.
3/8 = out of 8 people, 3 of them are boys.
x/160 = out of 160 people in a grade, x of them are boys.
So your final proportion would be 3/8 = x/160.
Bonus:
If you need to find the number of boys in a grade, just solve the proportion as normal, which would give you 60. So there are 60 boys out of 160 people in a grade.
