Due to the continental drift, the North American and European continents are drifting apart at an average speed of about 3.0 cm per year. At this speed, how long (in years) will it take for them to drift apart by another 1500 m (a little less than a mile)? Give answer in km.

Easy. Convert 3 cm to m (divide by 100 and therefore get 0.03) Divide 1500 by 0.03 (which gives you 50,000) right?

Wrong. I don't know how, nor do I know why, but apparently it's wrong. 50,000 yrs. at 3 cm a year gives you 1500m.

I know. The entire world has gone completely mad.