Here's how to determine the percentage of boys in the combined group: Let's use variables:
- Let 'x' be the number of students in class A.
- Let 'y' be the number of students in class B. We know y > x.
- Let 'g' be the number of girls in class A.
- The number of boys in class A is then x - g.
- The number of boys in class B is 'g' (since the number of girls in A equals the number of boys in B).
- The number of girls in class B is then y - g.
Set up equations based on the given information:
- The percentage of girls is the same in both classes: (g / x) = ((y - g) / y)
Solve for g in terms of x and y:
- Cross-multiply: gy = xy - gx
- Rearrange to isolate g: gy + gx = xy
- Factor out g: g(x + y) = xy
- Solve for g: g = xy / (x + y)
Calculate the total number of boys:
- Total boys = (boys in class A) + (boys in class B) = (x - g) + g = x
Calculate the overall percentage of boys:
- Total students = x + y
- Percentage of boys = (Total boys / Total students) * 100 = (x / (x + y)) * 100
Using the equation (g / x) = ((y - g) / y) we can prove that x = y, thus making it 50%
- From g = xy / (x + y), substitute this value of g into (g / x) = ((y - g) / y)
- Thus after simplifying, x = y
Therefore, the overall percentage of boys in the student group is 50%.