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.
Average rate of the function: 3
Step-by-step explanation:
The function in this problem is

The average rate of change of a function over an interval
is given by

where
are the values of the function calculated in
respectively
For the function in this problem we have:
, so

, so

So, the average rate of change is

Learn more about rate of change:
brainly.com/question/4152194
brainly.com/question/12941985
#LearnwithBrainly
Estimate:6000
You can use distributive property
Answer :
x = - 12 for y = - 4
Step-by-step explanation:
Given as y = - 6 when x = - 14
write in equation form
I.e y = x + c
Put x and y values ,
So, c = y - x
c = - 6 + 14 = 8
Now when y = - 4 and c = 8 ,
So, from eq x = y - c
∴ x = - 4 - 8 = - 12 Answer