A patient weights 223lbs and is put on a diet to lose 28 lns in 3 months. The patient loses 6 3/4 lbs the first month and 12 5/8 lbs the second month. How much weight must be lost in the 3rd month to reach his goal?

1. Convert first month's loss to improper fraction: 6 \frac{3}{4} = \frac{27}{4}

2. Convert second month's loss to improper fraction: 12 \frac{5}{8} = \frac{101}{8}

3. Convert \frac{27}{4} to \frac{54}{8} to add with \frac{101}{8} .

4. Total loss after two months: \frac{54}{8} + \frac{101}{8} = \frac{155}{8}

5. Total target loss is 28 lbs = \frac{224}{8}

6. Weight to lose in third month: \frac{224}{8} - \frac{155}{8} = \frac{69}{8}

7. Convert \frac{69}{8} to the mixed number: 8 \frac{5}{8}

Answer: 8\frac{5}{8}=8.625 lbs.