There are 8 pints in a gallon. It will take 10 days to drink 1 5-gallon container.
30 / 10 = 3
He will drink 3 containers. Hope this helped :)
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.
Multiply (4) (7x8) and you’ll get 7/2