To answer this question you would subtract the $250 deductible from $1400. The answer would be $1150 remaining After the deductible. You would then pay 10% of this $1150 for your cost. 0.10 times $1150 =$115. Add the $115 to the $250 deductible and your total cost would be $365.
So to get the $ spent on misc items, just add up the other expenses and subtract it from 3600:

Now to put them into fractions.
Tuition: 
Rent: 
Food: 
Misc: 
Hmm... well, here ya go.
1.50 ÷ 0.05 = 30
So, the total is $30
As for the tax rate, including the total, it would be $31.50.
Hope I helped.