There are ten 50 paise coins placed on a table. Six of these show tails, four show heads. A coin is chosen at random and flipped over (not tossed). This operation is performed seven times. One of the coins is then covered. Of the remaining nine coins, five show tails and four show heads. The covered coin shows
Explanation:
The initial reading for 10 coins is : 6 Tails and 4 Heads After repeating the process of flipping one coin at random for 7 times, the final reading for 9 coins is: 5 Tails and 4 Heads.
Therefore, possible final reading for 10 coins is: 6 Tails and 4 Heads or 5 Tails and 5 Heads. If the final reading is 6T and 4H, it is same as the initial one. However, this is not possible as the process of flipping a coin has taken place an odd number of times, so there has to be atleast one change in the final reading.
Therefore, the final reading is 5T and 5H.
So the covered coin will certainly be a Head.
Hence, option (a).
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