Answer :
there are 18 + 12 total students.
18 are girls and 12 are boys, since the total is 30 students, that's the amount of probable outcomes, and since there are 12 boys, that's the amount of favorable outcomes, thus
12/30 or 0.4, 0.4 * 100 is 40%.
18 are girls and 12 are boys, since the total is 30 students, that's the amount of probable outcomes, and since there are 12 boys, that's the amount of favorable outcomes, thus
12/30 or 0.4, 0.4 * 100 is 40%.