A retail establishment accepts either the American credit card or Visa credit card. A total of 30% of its customers carry an American Express card, 80% carry a VISA card, and 20% carry both.
1) Find the probability that a randomely selected customer carries at least one of the two credit cards. draw a Venn diagram and shade the region corresponding to at least one?
2) Find the probability that a randomely selected customer carries one, and only one, of the two credit cards. Draw a Venn diagram and shade the region corresponding to one and only one?
3) Given that a randomely selected customer is found to carry an American Express card, probability he or she carries a Visa?
4) Given a randomely selected customer is found to carry a Visa card, what is the probability he/she also carries an American Express card?
5) Are carrying an American Express card and carrying a VISA card independen?