<PRE><B>Question 178882</B>
a car travels 40 mph for 20 miles, 36 mph for 24 miles, and 48 mph for 16 miles. what is its average speed?
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Find the total distance:
20 + 24 + 16 = 60 miles.
Find the total time:
20 miles/40 mph = 0.5 hrs = 30 minutes
24 miles/36 mph = 2/3 hrs = 40 minutes
16 miles/48 mph = 1/3 hrs = 20 minutes
Time = 90 mins = 1.5 hours
Avg speed = 60 miles/1.5 hours
= 40 mph</PRE>