How do you create a word problem using unit rate?

Please check the explanation at this site --

http://www.321know.com/rat-unit-rate.htm

One of the most common word problems might be --

George averages 60 miles per hour when driving on a highway. How far will he go in three hours?

Can you create a word problem about apples? If one costs 50 cents, how much would a dozen apples cost?