The distance between a town and a factory is 30 km. A man started to walk from the factory to the town
at 6.30 am. While a cyclist left the town for the factory at 6.40 am riding at a speed of 18 km hr!, the man
met the cyclist after walking 6 km. Find at what time they met?
A) 7.30 am
B) 8.00 am
C) 8.10 am
D) 8.30 am
Answers
Answer:
please check option first
Explanation:
as man and cyclists meat at 6 km meant they both reach 6 km
so, distance reach by cyclists=6 km
as v =ds/dt
t=s/v
t=6/18
t=1/3 hr that means 20 minutes
so they met at 7 am .
Answer: (b) 8:00 AM
Explanation:
Forget that the man ever existed
Now come back to the cyclist because he is the priority
The time cyclist left the town at = 6:40 Am
his speed was 18 km/hr
change km/hr to m/s
multiply it by 5/18 (quick method of conversion from km/hr to m/s)
it will give you 5m/s
now 5m/s and cyclist covered 24 Km (Note, the MAN met him after 6 Km of walking, the cyclist thus travelled 30 - 6 = 24 Km)
distance = speed × time
time = distance/speed
time = 24000/5 (24Km = 24000m)
time = 4800 seconds
therefore time taken = 4800/60
= 80 minutes or 1 hour 20 minutes
therefore answer is (b) 8:00 AM
Hope this helps