are there any options or do i have to answer
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.
11 times the sum of a number and 15
11 * (x+15)
11(x+15)
the answer is D.
It is 45 because the triangle should be 180 degree and if K is 45 then J should be 45, too. We all know that the right triangle is 90 degree, so we add angle J and G, it is 135. Lastly, you subtract 180- 135=45.