-- Driving at 30 mph for 20 minutes (1/3 hour), you cover 10 miles.
-- Walking at 3 mph for 10 minutes (1/6 hour), you cover 0.5 mile.
-- Average speed = (total distance covered) / (time to cover the distance)
= (10.5 miles) / ( 1/2 hour)
= 21 miles per hour.
Answer: -5/4
Step-by-step explanation:
hmm. this tricky. i will let u know when i work it out. im doing school right now. sooo. yeah ill let ya know soon.