You need to first convert everything to a simple fraction, like 4/7, 3/5, etc.
After that just multiply the tops and bottoms separately.
Example:
3 3/4 x 3 3/4
Convert 3 3/4 to a simple fraction first
3 3/4 = 3 + 3/4 (same thing. think about measuring water in a cup. you would add 3 cups PLUS 3/4 of a cup). In order to add the fractions, you need to make them both have the same bottom part, so multiply the 3, which is really 3/1 too, by 4 on the top and bottom
3/1 = 4x3/4x1 = 12/4
12/4 + 3/4 = 15/4
A shortcut to doing this conversion is to just multiply the bottom number of the mixed fraction '4' in 3 3/4 by the whole number on the far left ('3') and add it to the top part of the fraction. 4x3 + 3 = 15. You then put it all over the bottom part, so 15/4.
Once you have 2 regular fractions, just add them up.
15/4 + 15/4 = 30/4 = 7 1/2
