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the ratio of boys to girls in Mr.Cunningham's class is 2 to 3. there is 18 girls in the class. how many boys are in the class

User Darc Nawg
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1 Answer

6 votes

Explanation:

If the ratio of boys to girls in the class is 2 to 3, this means that for every 2 boys, there are 3 girls.

Let's use the variable "x" to represent the number of boys in the class.

If the ratio of boys to girls is 2 to 3, then the ratio of boys to the total number of students in the class is 2 to 5

We know that there are 18 girls in the class, so the total number of students is:

18 girls + x boys = 18 + x students

And we also know that the ratio of boys to the total number of students is 2 to 5.

So we can set up the following proportion:

2/5 = x/(18 + x)

Cross-multiplying gives:

2(18 + x) = 5x

Expanding the left side gives:

36 + 2x = 5x

Subtracting 2x from both sides gives:

36 = 3x

Dividing both sides by 3 gives:

x = 12

Therefore, there are 12 boys in Mr. Cunningham's class.

User Almas Mahfooz
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