3. Suppose that you draw two cards from a standard 52 card deck. You replace the first card and shuffle thoroughly before you dr
aw the second. [p-4-9-45] a. What is the probability that the first card is 7? b. What is the probability that both cards are 7? c. What is the probability that the first card is not a 7? d. What is the probability that both cards are not 7?
You can multiply by 12 because to get rid of the fractions all terms should be divided by the LCM (ie the smallest multiple that is exactly divisible by 2, 4 and 3)
Multiples of 3 = 3, 6, 9, 12
Multiples of 4 = 4, 8, 12, 16
Multiples of 2 = 2, 4, 6, 8, 10, 12
Therefore the fractions should be multiplied by 12