Subject: mathqa
Question: on a trip , a cyclist averaged 11 miles per hour for the first 22 miles and 10 miles per hour for the remaining 20 miles . if the cyclist returned immediately via the same route and took a total of 9 hours for the round trip , what was the average speed ( in miles per hour ) for the return trip ?
Option: 
A: 8
B: 8.2
C: 8.4
D: 7.6
Answer: C