SOLUTION: 15 cards number 1 through 15 and two cards are drawn with replacement. a) find the probability tht both are less than 5 b) find the probability that the first is less than 5 and

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Question 611114: 15 cards number 1 through 15 and two cards are drawn with replacement.
a) find the probability tht both are less than 5
b) find the probability that the first is less than 5 and the 2nd is greater than 12.
[for a. I tired 5/15 x 5/15 = 1/9, but that is incorrect. For b. 5/15 x 12/15 = 4/15, which is also incorrect. Your explination is greatly appreciated. Thank you.
Answer by vleith(2983) (Show Source):
You can put this solution on YOUR website!
You are on the right track.
But you said there are 5 chances out of 15 that the card is less than 5. IN fact, there are only 4 chances (1, 2, 3 and 4) . The fifth card would be a 5, which is NOT less than 5.
so
For b, you have 4/15 at less than 5 and 3/15 at greater than 12

Do those match the answers??