Average speed = Total distance / Total time.
Total distance traveled by Joel = Distance covered in the first 3 hours + Distance covered in the next 5 hours.
Distance covered in the first 3 hours = 3 x 60 = 180 miles
Distance covered in the next 5 hours = 5 x 24 = 120 miles
Therefore, total distance traveled = 180 + 120 = 300 miles.
Total time taken = 3 + 5 = 8 hours.
Average speed = 300/8 = 37.5 mph.
we know that 1 mile = 1.6 kms
=> 37.5 miles = 37.5 x 1.6 = 60 kms
Average speed in Kmph = 60 kmph.
Speed on return trip = 150% of 50 = 75 km/hr.
Average speed = (2 x 50 x 75)/(50 + 75) = 60 km/hr.
Here distance d = 800 mts
speed s = 63 - 3 = 60 kmph = 60 x 5/18 m/s
time t = = 48 sec.
In 1hr, the bus covers 60 km without stoppages and 40 km with stoppages.
Stoppage time = time take to travel (60 - 40) km i.e 20 km at 60 km/hr.
stoppage time = 20/60 hrs = 20 min.
let, speed of Ali=X mph and Faizer=Y mph
Now, relative speed when Ali is walking int the same direction with Faizer= (X-Y)mph
hence, according to question, 27/(X-Y)=9 ; solving X-Y=3; --- (1)
Now relative speed when walking in the opposite direction= (X+Y) mph
hence, according to question, 27/(X+y)=3; solving X+Y=9; --- (2)
solving 1 and 2 we get X=6 and Y=3, where X is the speed of Ali.
Average speed=total distance/total time
Let distance to store be K
then, total time =(K/20)+(K/30)=K/12
and, total time =(2K)
so average speed= 2K / (K/12) = 24kmph.
Speeds of two trains = 30 kmph and 58 kmph
=> Relative speed = 58 - 30 = 28 kmph = 28 x 5/18 m/s = 70/9 m/s
Given a man takes time to cross length of faster train = 18 sec
Now, required Length of faster train = speed x time = 70/9 x 18 = 140 mts.
Comments
There are no comments.Copyright ©CuriousTab. All rights reserved.