Question

A raffle jar contains 10 purple tickets, 7 blue tickets, and 4 red tickets. What is the probability of randomly selecting a blue ticket, and without replacing it, then randomly selecting a purple ticket? A.2/21 B.1/10 C.1 /7 D. 1/6

Answer 1

You have 7 blue tickets and 21 total.
So the odds of pulling a blue ticket is 7
21
If you replace the ticket, the total number of tickets changes, so the total is 20 tickets.
The odds of pulling a purple ticket is 10
20
So the odds that you pull a blue, replace it, then pull a purple is:
7 * 10 = 70 = 1
21 20 420 6
so your answer is 1/6 or D