Give the step-by-step reasoning process and then the final answer. A hand-crank pencil sharpener can sharpen one pencil every forty-five seconds. An electric version can sharpen one in twenty seconds. How many more pencils can the electric sharpener sharpen than the hand-crank sharpener in six minutes?
A minute is 60 seconds, so 6 minutes is 6 * 60 = 360 seconds. A hand - crank sharpener can sharpen 360 / 45 = 8 pencils in 6 minutes. An electric sharpener can sharpen 360 / 20 = 18 pencils in 6 minutes. Therefore, an electric sharpener can sharpen 18 - 8 = 10 more pencils than a hand - crank in 6 minutes.
The final answer: 10.