The question does not seem complete, but I'll represent the statement mathematically and look for their ages each. This is because the worst they can ask for is their ages.
Let C stand for Courtney's age, A for Andrei's age, N for Natalie's age and S for Shari's age. From the question we can deduce the following:
C = 2A
C = N + 3
C = S/2
S - N = C + A
S = 2C, N = C - 3 and A = C/2, therefore we have
2C - (C - 3) = C + C/2
C + 3 = C + C/2
C/2 = 3 and C = 6
A = C/2
A= 6/2
A = 3
N = C - 3
N = 6 - 3
N = 3
S = 2C
S = 2 x 6
S = 12.
C = 6, A = 3, N = 3 and S = 12
Answer:
The answer is 30
Step-by-step explanation:
If you were to do 50% of 30, it would be 15 students that are girls. There's 18 students that are girls though, so the extra 10% would make 18 students in the class girls. The remaining 40% would be 12 boys. So basically you're taking 10% from one side and putting it in the other because 50% of 30 is 15 (well this is at least how I would do it, I don't know how others would do it though)
Add those together is 7/10
