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The ratio of boys and girls in a class with 40 students = 3:2. If 4 new boys are added, what will be the new ratio?

User Cjol
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2 Answers

2 votes

Answer:

7:11

Explanation:

We know the total number of students and the ratio of boys to girls. The total for the ratio of boys and girls would be 5 (3+2). Now we can set up proportions knowing these numbers.

b = 3

g =2

t =5

Let's find out how many actual boys there are by setting up a proportion

3/5 = b/40

I will look at the denominators to find x. 5 times what gives me 40? (8). So, I will multiple the top number (numerators). Since I need to multiple the bottom number by 8 to get the number 40, I will now multiple the top number by 8 and get 24.

Now, I know how many actual boys and girls were in the original class. There were 24 boys, 16 girls (40 - 24) and 40 total students.

Now I will take this new information and apply it to the new situation. Now I have 28 boys (24 + 4) and a new total 44.

The ratio of boys to girls would not be 28: 16 or 7:4

User Dakur
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3.7k points
2 votes

Answer: 7:4

Explanation:

40 boys and girls 3:2 = 24 boys + 16 girls

4 boys are added 28 boys + 16 girls /4 = 7:4

User MaanooAk
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3.2k points