Question

At 2:00pm a car's speedometer reads 20mph, and at 2:10pm it reads 30mph.

Answer 1

Over this 10-minute interval, the car's average acceleration is

$\dfrac{30\,\mathrm{mph}-20\,\mathrm{mph}}{10\,\mathrm{min}}=\dfrac{10\,\mathrm{mph}}{\frac16\,\mathrm h}=60\dfrac{\rm mi}{\mathrm h^2}$

The MVT says that at some point during this 10-minute interval, the car must have had an acceleration of 60 mi/h^2.