OA coming after a few people answer..
An express train traveled at an average speed of 100 kilometers per hour, stopping for 3 minutes after every 75 kilometers. A local train traveled at an average speed of 50 kilometers, stopping for 1 minute after every 25 kilometers. If the trains began traveling at the same time, how many kilometers did the local train travel in the time it took the express train to travel 600 kilometers?
a. 300
b. 305
c. 307.5
d. 1200
e. 1236
Difficult Math Problem #16
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600 = 8 * 75
so there were 7 stopps of 3 minutes and 8 rides that took (75/100)*60 = 45 min
total jurney was 8*45+21 = 381 min
the local train takes 30min to pass 25Km + 1minute
so 381/31 = 12*31 + 8 minute
so the local train would pass 12*25 + (8/60)*50 =~ 306.6
* if i would add to this 3 minute, i would get 307.5, but i think the accurate answer is 300.666
so: C
so there were 7 stopps of 3 minutes and 8 rides that took (75/100)*60 = 45 min
total jurney was 8*45+21 = 381 min
the local train takes 30min to pass 25Km + 1minute
so 381/31 = 12*31 + 8 minute
so the local train would pass 12*25 + (8/60)*50 =~ 306.6
* if i would add to this 3 minute, i would get 307.5, but i think the accurate answer is 300.666
so: C
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i ment 382/31 = 12 + 9 min
and (9/60)*50 = 7.5
so the answer is indeed: 307.5
final post from me on this thread
and (9/60)*50 = 7.5
so the answer is indeed: 307.5
final post from me on this thread
600/75 = 8 so the train in all had to come across 7 stations by the last 8th station it covered the 600 kilometers so no halting time.
7stations * 3mins = 21 mins THe total time the train halted
75 kms it covers in 45 mins , which is the journey for 1 station
so in all 45 *8 = 360 mins
In all time 360 +21 = 381
For local train,
50kmph so it travels 25 kmph in 30 mins + a 1 min break
so in 31 mins it travels 25 km
mins - km
31 - 25
381 - x
so x= 381*25/31= ~ 307[Anyone knows a better way to calculate this]
OR a better way to solve this. Btw Ans C
7stations * 3mins = 21 mins THe total time the train halted
75 kms it covers in 45 mins , which is the journey for 1 station
so in all 45 *8 = 360 mins
In all time 360 +21 = 381
For local train,
50kmph so it travels 25 kmph in 30 mins + a 1 min break
so in 31 mins it travels 25 km
mins - km
31 - 25
381 - x
so x= 381*25/31= ~ 307[Anyone knows a better way to calculate this]
OR a better way to solve this. Btw Ans C
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OA:
the answer is C: 307.5 km
Express Train:
600 km --> 6 hours (since 100 km/h) + stops * 3 min.
stops = 600 / 75 = 8, but as it is an integer number, the last stop in km 600 is not a real stop, so it would be 7 stops
so, time= 6 hours + 7 * 3 min. = 6 hours 21 min
Local Train:
in 6 hours, it will make 300 km (since its speed is 50 km/hour)
in 300 km it will have 300 / 25 stops = 12, 12 stops 1 min each = 12 min
we have 6 hours 12 min, but we need to calculate how many km can it make in 6 hours 21 min, so 21-12 = 9 min
if 60 min it can make 50 km, 9 min it can make 7.5 km
so, the distance is 300 + 7.5 = 307.5 km
the answer is C: 307.5 km
Express Train:
600 km --> 6 hours (since 100 km/h) + stops * 3 min.
stops = 600 / 75 = 8, but as it is an integer number, the last stop in km 600 is not a real stop, so it would be 7 stops
so, time= 6 hours + 7 * 3 min. = 6 hours 21 min
Local Train:
in 6 hours, it will make 300 km (since its speed is 50 km/hour)
in 300 km it will have 300 / 25 stops = 12, 12 stops 1 min each = 12 min
we have 6 hours 12 min, but we need to calculate how many km can it make in 6 hours 21 min, so 21-12 = 9 min
if 60 min it can make 50 km, 9 min it can make 7.5 km
so, the distance is 300 + 7.5 = 307.5 km