Answer:
19 1/18 miles.
Explanation:
For Tuesday's ride we need to multiply 10 8/9 by 3/4.
10 8/9 = (9*10+8) / 9 = 98/9 miles.
98 / 9 * 3/4
= 98/3 * 1/4
49/6
= 8 1/6 miles.
Total miles over 2 days = 10 8/9 + 8 1/6
= 18 + 8/9 + 1/6
= 18 + 48/54 + 9/54
= 18 57/54
= 19 3/54
= 19 1/18 miles.