Arestaurant uses 80% of its oil in one week. they now have 36 quarts of olive oil left. how do you use a double number line to find the number of quarts the restaurant had at the beginning of the week

Due to a packaging error, 4 cans labeled diet soda were accidentally filled with regular soda and placed in a 12 pack carton of diet soda. two cans were randomly selected from this 12 pack. what is the probability that both cans were regular soda?