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A drawer contains 5 brown socks and 4 blue socks well mixed a manreaches the drawer and pulls out socks at random. What is the probabilitythat they match?`4//9`b. `5//8`c. `5//9`d. `7//12`A. `4//9`B. `5//8`C. `5//9`D. `7//12` |
Answer» Correct Answer - A Out of 9 socks, 2 can be drawn in `.^(9)C_(2)` ways. Therefore, the total number of cases is `.^(9)C_(2)`. Two socks drawn from the drawer will match if either both are brown or both are blue. Therefore, favorable number of cases is `.^(5)C_(2) + .^(4)C_(2)`. Hence, the required probability is `=(.^(5)C_(2) + .^(4)C_(2))/(.^(9)C_(2)) = (4)/(9)` |
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