20 + 40x = 260
40x = 260 - 20
40x = 240
x = 240/40
x = 6 fulltime employees needed
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A=πr^2s/360 multiply both sides by 360
360A=sπr^2 divide both sides by πr^2
s=360A/(πr^2)
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:
B
Step-by-step explanation:
2/8 = 1/4 = 0.25
