For this case we convert the mixed numbers into improper fractions:
[tex]7 \frac {1} {3} = \frac {3 * 7 + 1} {3} = \frac {21 + 1} {3} = \frac {22} {3} = 7.33\\8 \frac {5} {9} = \frac {9 * 8 + 5} {9} = \frac {72 + 5} {9} = \frac {77} {9} = 8.56[/tex]
So, subtracting we have:
[tex]8.56-7.33 = 1.23[/tex]
So we have to see that Lee was 1.23 minutes faster than his friend.
Answer:
Lee was 1.23 minutes faster than his friend.