Error Analysis: Mr. Hasson is buying a new bike for the summer time. The bike originally costs $150 but he sees it's on sale for 30% off. Mr. Hasson thinks that this means the price is $149.70 because 30% means 0.30 and 150 - 0.30 = $149.70.
What is the error that Mr. Hasson made?
What is the correct way to calculate the sale price?