A car averages 55 mph for the first 4 hours of a trip and
averages 70 mph for each additional hour. The average speed
for the entire trip was 60 mph. How many hours long is the trip?

Answer Posted / kondayya

we have
(55*4+70*x)/(4+x)=60
by trial and error method,
put x=1,x=2,........
ans=2

Is This Answer Correct ?    9 Yes 10 No



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