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
A fact family is basically just different equations with the same numbers getting the same/different numbers as answers you might say...
this will make more sense:
5x8=40
8x5=40
40/8=5
40/5=8
It is Wednesday as it has the highest fraction of homework i.e
Monday has 0.7 of homework for her classes
Tuesday has 0.6
Wednesday has 0.81
Thursday has 0.5.
Therefore it has to be Wednesday.
Hope this helps :).