convert 3 6/2 to an improper fraction so: 12/2
convert 2 4/5 to 14/5
multiply the numerators of the improper fractions so 12*14, which is 168.
multiple the denominators so 2*5, which is 10.
the new fraction is 168/10, so you divide 168 divided by 10, which is 16.8, or 16 4/5.