<PRE><B>Question 902717</B>
A car is traveling at 30 mph and starts to accelerate to reach 40 mph. It reaches 40 mph 10 seconds later after traveling 250 feet. What was the cars average acceleration. 
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change mi/hr to ft/sec
30 mi/hr = 44 ft/sec
40 mi/hr = 176/3 ft/sec
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acc = (176/3 - 44)/10 ft/sec/sec = 22/15 ft/sec/sec
The 250 feet is not a factor, and might not be true.

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In other what speed would the car have to travel in that timeframe to reach 40 mph?
idk what that means.</PRE>