multiply the numerators then divide the denominators
for example
1\2 x 3\4
(1 x 3=3)
(2 x 4=8)
answer=3\4
in division ,write the first equation,change the sign and then reciprocate the second equation.
for example
1\2 divided by 3\4
1\2 x 4\3
answer=2\3