umesh menon

• Jun 8th, 2006

 

total no of steps =50*3+75*1=150+75=225

total time taken 1 step =3 step =2 steps diff

225/2=112.5 while moving

when stopped 112.5/50=2.25

112.5/75=1.25

time taken by first person > time taken by second person (proof)

Ravinder G

• Jun 23rd, 2006

 

Solution (not sure):

If A takes 1 step in one second, then B takes 3 steps in one second. If A takes t1 seconds to

take 50 steps, then B takes 150 steps in t1 seconds.

For B, to take 150 steps he requires t1 seconds,

then to take 75 steps he requires t1/2 seconds.

So now, s1=50, t1 = t1 & s2=75, t2=t1/2

ans= (s1*t2 ~ s2*t1) / (t1 ~ t2) which gives 100.

so 100 steps is the answer

Himanshu kapoor

• Jul 10th, 2006

 

sorry to say no one give the correct approach to this problem

You have to use relative velocity concept to solve this problem and this types of problems

solution:

Let L be the steps of the stationary escalator and v be the velocity of the

the escalator steps/second (and that is constant for both the person).

Now

If A takes 1 step in one second, then B takes 3 steps in one second. If A takes t1 seconds to

take 50 steps, then B takes 150 steps in t1 seconds.

For B, to take 150 steps he requires t1 seconds,

then to take 75 steps he requires t1/2 seconds.

now use relative velocity

L - v*t1=50 (for first person)

L-v*t1/2=75(for second person)

S(escalator w.r.t ground)-s(person w.r.t escalator)=s1(person w.r.t ground)

S,s,s1 are the steps

now put the v*t1 from 1 into the second equation and u get

L- (L-50)/2=75

L+50=150

L=100;

 

sathwika.G

• Feb 14th, 2021

 

total distance(total number of steps)=steps taken by A+ steps taken by escalator=50+x.t1(x is speed of escalator and t1 is time)
total distance(total number of steps)=steps taken by B +steps taken by escalator=75+x.t1/2(t1/2 is time with respect to b)
while escalator is stationary both are equal
50+xt1=75+x.t1/2
by solving x.tl=50
substitute x.t1=50 in total distance i.e 50+50=100
_______Note: you may get a doubt how t1 and t1/2 are taken_________
suppose A takes 50 steps in t1 seconds then in same t1 seconds B takes 150 steps(50*3 as mentioned B takes 3 steps while A takes 1 step)
t1 for 150
? for 75 => we get t1/2