5 White Socks and 3 Black socks are in a drawer. I take out two socks. What is the probability the socks are the same colour?
Problem Tackles: Counting Probabilities, Non-replacement probability problems. Keeping track of events
Total number of socks: 5 + 3 = 8Scenarios: Could pick two white socks or two black socksP(Picking two white Socks) = 5/8 * 4/7 = 20/56 . (Number of socks after first pick is 7, number of white socks left is 4)P (Picking two Black socks) = 3/8 *2/7 = 6/56 (same idea as above)P(picking two socks of same colour) = P(Picking two white socks) + P(Picking two black socks) = 6/56 + 20/56 = 26/56
BS
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