Answer:

Explanation:
First, since the fraction part of 5 3/4 ( 3/4 ) the denominator or the bottom number will be the bottom of the fraction.. :

Now lets multiply 5x4=
20…
Now remember that the original number was 5 3/4, well since there was a 3 on top of the 4 ( or the numerator ) were gonna add:
20+3=
23…
Put 23 on top of 4..

Boom! There you go!