Changing mixed number to an improper fraction

Example: 5 3/4

You take the whole number (which is 5) and multiply it by the bottom number or denominator (which would be 4) and add the top number or numerator (which would be 3) 23/4

Example:
3 1/2 
You multiply 3 times the denominator and add that to 1, and the denominator would be 2.
7/2