a. train traveling at 79 km/hr crosses a man going in the same direction at 7 km/hr in 12 seconds if the man crosses a woman coming from the. opposite direction in. 10 seconds then the speed in km/hr the woman is
Answers
Step-by-step explanation:
MATHS
Two men are running in the same direction with a speed of 6 km/hr and 7
2
1
km/hr. A train running in the same direction crosses them in 5 sec and 5
2
1
sec respectively. The length and the speed of the train are
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ANSWER
Let the length of the train be l m and its speed be x km/hr
Then relative speed of train w.r.t. 1
st
man
=(x−6) km/hr
=(x−6)×
18
5
m/s
Relative speed of train w.r.t 2
nd
man =(x−7.5) km/hr = (x−7.5)×
18
5
m/s
Length of the train = Distance travelled in both the cases
⇒(x−6)×
18
5
×5=(x−7.5)×
18
5
×5.5
⇒(x−6)×5=(x−7.5)×5.5
⇒5x−30=5.5x−41.25
⇒0.5x=11.25
⇒x=
0.5
11.25
=22.5 km/hr
∴ Length of the train = ((22.5−6)×
18
5
×5)m=22.92 m (approx)
Answer:
ans is
7.4 km per hour ..............