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3 years ago

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A test driver has to drive a car on a 1-mile track for two rounds in a way, that his average speed is 60 mph. On his first round

his average speed is 40 mph. How fast does he need to drive, to get the right speed average?

1 answer:

Darya [45]3 years ago

3 0

(40+x)/2=60

40 +x = 120

x = 80

check :

40+80 = 120

120/2 = 60

so his second round needs to be 80 mph

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