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प्रश्न
A coin is tossed 8 times, how many different sequences containing six heads and two tails are possible?
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उत्तर
When tossing a coin, the possible outcomes are head
and tail.
Total number of outcomes of heads and tails on tossing a coin 8 times is
= 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2
= 28
The number of ways of getting six heads and 2 tails
= `(8!)/(6! xx 2!)`
= `(8 xx 7 xx 6!)/(6 xx 2 xx 1)`
= 4 × 7
= 28 ways
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