1. The cup can hold 7/9 of a pint. Emily pours in 2/3 of a pint. To find how much milk can be added, subtract the coffee from the total capacity: 7/9 - 2/3. Convert 2/3 to ninths: 2/3 = 6/9. Then, 7/9 - 6/9 = 1/9. A customer can add 1/9 of a pint of milk.
2. One pitcher has 3/8 liter and the other has 5/12 liter. To find the total, add the fractions: 3/8 + 5/12. The least common denominator is 24. Convert: 3/8 = 9/24 and 5/12 = 10/24. Add them: 9/24 + 10/24 = 19/24. There is 19/24 liter of milk altogether.
3. Two large cookies weigh 2 × 5/6 oz = 10/6 oz. One small cookie weighs 4/9 oz. To find the total weight, add: 10/6 + 4/9. The least common denominator is 18. Convert: 10/6 = 30/18 and 4/9 = 8/18. Add them: 30/18 + 8/18 = 38/18. Simplify: 38/18 = 19/9 or 2 1/9 oz. The total weight is 19/9 oz (or 2 1/9 oz).
4. The bigger bag is 4/5 kg and the smaller is 7/12 kg. To find how much more the bigger bag has, subtract: 4/5 - 7/12. The least common denominator is 60. Convert: 4/5 = 48/60 and 7/12 = 35/60. Subtract: 48/60 - 35/60 = 13/60. The bigger bag has 13/60 kg more coffee.
5. The first cheesecake has 3 slices left out of 16, which is 3/16. The second cheesecake had 10 slices, 4 were sold, so 6 are left, which is 6/10 or 3/5. To find the total cake left, add: 3/16 + 3/5. The least common denominator is 80. Convert: 3/16 = 15/80 and 3/5 = 48/80. Add them: 15/80 + 48/80 = 63/80. There is 63/80 of a cheesecake left in the fridge.
6. The bag originally had 4/5 kg. The chef used 1/10 kg for the can and 3/20 kg for the cake. Total used: 1/10 + 3/20. The least common denominator is 20. Convert: 1/10 = 2/20. Add: 2/20 + 3/20 = 5/20 = 1/4 kg. Subtract from original: 4/5 - 1/4. The least common denominator is 20. Convert: 4/5 = 16/20 and 1/4 = 5/20. Subtract: 16/20 - 5/20 = 11/20. There is 11/20 kg of sugar left in the bag.
Parent Tip: Review the logic above to help your child master the concept of fraction worksheet word problems.
