A store manager gathers some demographic information from the store's customers. The following chart summarizes the age-related information they collected:

Age	Number of Customers
<20<20	53
20-29	50
30-39	56
40-49	72
50-59	52
6060	84

One customer is chosen at random for a prize giveaway. (Round answers to 4 decimal places.) a. What is the probability that the customer is at least 20 but no older than 59? b. What is the probability that the customer is either older than 60 or younger than 30? c. What is the probability that the customer is at least 60?