Let's V the speed of the girl in step
v the speed of the escalator in step
L the length between ground and floor.
V*60+v*60=L ==> V+v=L/60
V*90-v*90=L ==> V-v=L/90
2V=L(3+2)/180
==>V=5L/360
Time to climb (in step) with v=0 (escalator standing still)
V*t=L==> t=L/V=L/(L*5/360)=72
The girl will count 72 steps.
Answer:
D, 30 ft
Step-by-step explanation:
Wait what does the question say 4 me it's blurry
111+496= 607
1/10 + 1/10 = 2/10
607 + 2/10 = 607 and 2/10
But if youre just doing an approximate answer then...
111 = 110
496 = 500
So it would be 610
You can make 2/10 to 1/5 but that wouldnt be approx.
Your answer should be 610 and 2/10
