t = actual time racing along the road
22/60 = .367 hour
tend - tbegin = (t +.367)hr
and
d/(t+.367) = 77.8
but
d/t 89.5
so
d = 89.5 t
and
89.5 t/(t+.367) = 77.8
89.5 t = 77.8 t + 28.5
t = 2.438 hr driving
t+ .367 = 2.805 hr
= 2 hours and 49 minutes
Help with this please. No idea.
Except for a 22.00 min. rest stop, Emily drives with a constant velocity of 89.5 km/hr north. How long does the trip take if Emily's average velocity is 77.8 km/hr north?
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