Claire spends 1/2+1/4+1/3 on necessities, so we find a common denominator:
1/2=6/12
1/4=3/12
1/3=4/12
Then we add of these fractions together:
6/12+3/12+4/12=13/12
It looks like Claire is over-budget with her purchases.
(I’m not really sure if that is the problem)
Maybe it’s 1/2+1/8+1/24=12/24+3/24+1/24=16/24
This simplifies to 2/3 (dividing by 8).
So if Claire spends 1/2 on food, 1/4 of what’s left on rent, and 1/3 of that on power bills, then she will have 1/3 (1-2/3) left of her monthly salary.
I resaltó hope this helps!