Billy Bob loves cake. So his mom made him one, but the dog ate 78% of it. Then Billy ate 45% of the 22% that the didn't eat, how much is left? Simplified to the lowest terms as a fraction.
Of the 22% remaining, Billy Bob ate 45%, which means that 55% of the 22% remains, or:
22% x 55% =12.1% of the original cake remains.