Rule 12: To multiply a whole number and a fraction, complete the following steps.
Example 1: Multiply .
Answer. Convert the 7 to the fraction . Then we have
Multiply the numerators and the denominators, but leave them in factored form .
Factor the numerator and denominator and look for the fractions that have a value of 1. We have
Now prove to yourself with your calculator that your answer is correct. Calculate 4 divided by 21 and multiply the answer by 7. Now calculate 4 divided by 3. If you are correct, the answers are the same (equivalent) and you have successfully multiplied a whole number by a simple fraction.