Answer : Option B

Explanation :

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Solution 1
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Total number of outcomes possible when a coin is tossed = 2 (∵ Head or Tail)
Hence, total number of outcomes possible when 5 coins are tossed, n(S) = 2⁵
E = Event of getting exactly 2 heads when 5 coins are tossed
n(E) = Number of ways of getting exactly 2 heads when 5 coins are tossed = ⁵C₂

$MF#%\text{P(E) = }\dfrac{\text{n(E)}}{\text{n(S)}}= \dfrac{5_{C_2}}{2^5}=\dfrac{\left(\dfrac{5 \times 4 }{2 \times1}\right)}{2^5} = \dfrac{5 \times 2}{2^5} = \dfrac{5}{2^4}
= \dfrac{5}{16}$MF#%

If n fair coins are tossed,

Total number of outcomes in the sample space = $MF#%2^n$MF#%

The probability of getting exactly r-number of heads when n coins are tossed = $MF#%\dfrac{n_{C_r}}{2^n}$MF#%