On the same day at school, 1/6 of the students were wearing skirts and 5/8 of the students were wearing pants. the rest of the students were wearing shorts. what fraction of the students were wearing shorts?

What you do is you find the common denominator between the two fractions given.  the easiest is to just multiply them 

6*8=48

and then multiply each numerator by the number it's denominator is multiplied by

1*8=8  and 5*6=30

and now you have your new fractions, add them together

8/48+30/48=38/48

this leaves 10/48 as the people who were wearing shorts,  just simplify this and it's done

10/2    =5/24
48/2