17 if you maintain the ratio of 2:1 for bread and cheese, but you would get a remainder of 7 cheese slices. You could, however, cut up the extra pieces of cheese and add ~0.41 slices of cheese to each sandwich, which would melt into the rest of the cheese if you are grilling the sandwich. Otherwise, it's just an extra chunck, which is perfectly fine.
First you take 15/10 and see that you can take 5 out of the top and bottom, so it would become 3/2. Now you have 2 3/2. 2 goes into 3 once with 1 remainder so 3/2= 1 1/2
So then you take the original 2 and add it to 1 1/2. The answer is now 3 1/2
You will want to subtract the amount he ran on Monday from the amount on Tuesday. In order to subtract fractions, we must set them to the same denominator (bottom number). In order to do this, we must multiply 3/5 by 6/6 (the denominator on tuesday) which gets us 18/30. Then, for Tuesday, we must multiply 2/6 by 5/5 (the denominator on Monday) which is 10/30. Now, we can do Monday-Tuesday, 18/30-10/30 which gets us 8/30, if we simplify this, we get 4/15 :)
