1. **State the problem:** We need to find who has finished exactly $\frac{4}{5}$ of their project by adding the fractions of the project they completed last week and yesterday. 2. **Formula and rules:** To find the total fraction completed, add the fractions: $$\text{Total} = \text{Fraction last week} + \text{Fraction yesterday}$$ Make sure to find a common denominator when adding fractions. 3. **Calculate Jake's total:** $$\frac{7}{15} + \frac{1}{6} = \frac{7}{15} + \frac{1}{6} = \frac{14}{30} + \frac{5}{30} = \frac{19}{30}$$ 4. **Calculate Tom's total:** $$\frac{3}{6} + \frac{3}{10} = \frac{1}{2} + \frac{3}{10} = \frac{5}{10} + \frac{3}{10} = \frac{8}{10} = \frac{4}{5}$$ 5. **Calculate Felipe's total:** $$\frac{4}{7} + \frac{1}{4} = \frac{16}{28} + \frac{7}{28} = \frac{23}{28}$$ 6. **Calculate Bill's total:** $$\frac{6}{9} + \frac{1}{8} = \frac{2}{3} + \frac{1}{8} = \frac{16}{24} + \frac{3}{24} = \frac{19}{24}$$ 7. **Compare totals:** Jake: $\frac{19}{30} \approx 0.633$ Tom: $\frac{4}{5} = 0.8$ Felipe: $\frac{23}{28} \approx 0.821$ Bill: $\frac{19}{24} \approx 0.792$ 8. **Answer:** Tom has finished exactly $\frac{4}{5}$ of his project.