Let
s = number of steps in the escalator
v = velocity of the escalator in steps/second
The first day, the businessman made 20 steps. To bring him to the top, the escalator will do (s - 20) steps for him. It all happened in 20 seconds
$s - 20 = 20v$
$s - 20v = 20$ ← Equation (1)
The next day, the businessman made 32 steps, the escalator did (s - 32) steps for him bringing him to the top. 32 steps at 2 steps/second, it all happened in 16 seconds.
$s - 32 = 16v$
$s - 16v = 32$ ← Equation (2)
From Equations (1) and (2)
s = 80 and v = 3 ← Answer: [ A ]
