Consider the question. Archie is playing with his marbles outside. He loses 60% of them into the street. Of the remaining ones, he loses half down a sewer. If he has 20 left, how many did he start with?
 What is the step-by-step reasoning process to arrive at the answer: 100?
He had 40 before losing them into the sewer because 20 x 2 = 40. He started with 100 because 40 / .4 = 100.