Final answer:
To find the number of boys and girls in the class, let's assign variables B and G. We can write two equations using the given information and solve for B and G. There are 12 boys and 30 girls in the class.
Step-by-step explanation:
To find the number of boys and girls in the class, let's assign variables. Let B represent the number of boys and G represent the number of girls.
From the problem, we know that the number of boys is (2/5) of the girls. This can be written as:
B = (2/5)G
We also know that the total number of students in the class is 42. So we can write:
B + G = 42
Now we can use these two equations to solve for the values of B and G. First, let's solve for B in terms of G by substituting (2/5)G for B in the second equation:
(2/5)G + G = 42
Next, let's combine like terms:
(7/5)G = 42
To isolate G, we can multiply both sides of the equation by the reciprocal of (7/5), which is (5/7):
((7/5)G) * (5/7) = 42 * (5/7)
Simplifying, we get:
G = 30
Finally, we can substitute G=30 into the first equation to find B:
B = (2/5) * 30
Simplifying, we get:
B = 12
Therefore, there are 12 boys and 30 girls in the class.