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The only socks in Jerry’s drawer are 245 black socks and 246 green socks. Without looking, how many socks does he have to pull out in order to have a matching pair?

A) 2 socks
B) 3 socks
C) 246 socks
D) 491 socks

User Buzjwa
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1 Answer

7 votes

Final answer:

Jerry needs to pull out 3 socks to guarantee a matching pair. The probability calculations are based on the number of each color jelly bean divided by the total number of jelly beans.

Step-by-step explanation:

To ensure having a matching pair of socks, Jerry needs to pull out at most 3 socks. This is because, after pulling out two socks, there are two possibilities. Either he has pulled out two socks of the same color, in which case he already has a matching pair, or he has pulled out one black sock and one green sock. If he pulls out a third sock, it must either match the black sock or the green sock, guaranteeing a matching pair regardless of the color of the third sock.

Now, let's address the probability questions. The probabilities for selecting a jelly bean of each color can be computed as the number of jelly beans of that color divided by the total number of jelly beans in the jar.

  • P(B) (probability of getting a blue jelly bean) = 26/150.
  • P(G) (probability of getting a green jelly bean) = 20/150.
  • P(P) (probability of getting a purple jelly bean) = 28/150.
  • P(R) (probability of getting a red jelly bean) = 22/150.
  • P(Y) (probability of getting a yellow jelly bean) = 38/150.
  • P(O) (probability of getting an orange jelly bean) = (the rest of the jelly beans in the jar)/150.
User Alireza Mazochi
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