Jane travel a distance of 60 miles @ 30 mph and another 90 miles @ 60 mph. What is her average speed for the entire journey (in mph)?
A) 40
B) 42.8
C) 45
D) 52.3
E) 54.7
need helppppppp
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30 Second Hack:
Since Jane spent 2hrs traveling at 30mph, and 1.5hrs traveling at 60mph, her average speed (a weighted average) must be closer to 30mph than to 60mph. 45 is halfway between the two (it's the average), so the answer must be less than 45.
Guess A or B.
40 is the only 'round' answer choice. Not likely to be correct.
Guess B.
Since Jane spent 2hrs traveling at 30mph, and 1.5hrs traveling at 60mph, her average speed (a weighted average) must be closer to 30mph than to 60mph. 45 is halfway between the two (it's the average), so the answer must be less than 45.
Guess A or B.
40 is the only 'round' answer choice. Not likely to be correct.
Guess B.
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