A fraction or mixed number times a whole number
3 × 2/5 means three pieces of size 2/5: 2/5 + 2/5 + 2/5 = 6/5. So to multiply a whole number by a fraction, multiply the whole number by the numerator and keep the denominator: 3 × 2/5 = (3 × 2)/5 = 6/5 = 1 1/5. Simplify the answer when you can: 4 × 3/8 = 12/8 = 3/2 = 1 1/2. For a mixed number, multiply the whole part and the fraction part separately and add: 3 × 2 1/4 = 3 × 2 + 3 × 1/4 = 6 + 3/4 = 6 3/4. You can also change the mixed number into an improper fraction first: 2 1/4 = 9/4 and 3 × 9/4 = 27/4 = 6 3/4.
Rice portions. Use a cup and a pot of dry beans or rice. If one portion is 3/4 of a cup, measure out 5 portions by filling 3/4 of a cup five times (or filling a cup three times and counting quarters). Write the product as a fraction and as a mixed number, then check with the measured amount.