A plane flies along the four sides of a square ground at speeds of 100, 200, 300, and 400. What is plane's average speed in the whole trip?
(A) 250
(B) 192
(C) 150
(D) 124
(E) 108
plane flies along
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- sanju09
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- bpgen
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Absolutely right, we should not just do the Arithmetic(mean) of all those speeds.
We need to find out time spent during each different speeds and then divide total distance by total time.
We need to find out time spent during each different speeds and then divide total distance by total time.
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