Why do units of acceleration have two time units?

Answer 1

Acceleration = (v - u)/t

Replace each variable in the equation with their units

Acceleration = (m/s - m/s) / s

Same common denominator

(m - m/s)/s

Apply divison of fractions

(m-m)/s*s

(m/s^2)

Note: I know m - m = 0 but they are just units expressing metres!