A coin is tossed times. The probability of getting head atleast once is greater than , then the least value of is
An explanation for the correct option:
Step 1: Find the probability of getting head and getting tail.
We have been given that, a coin is tossed times.
We need to find the value of when the probability of getting head at least once is greater than
The probability of getting head is,
The probability of getting tail is,
Step 2: Find the probability of getting no head after tosses.
Let be the number of heads getting in tosses.
We have been given that, the probability of getting head at least once is greater than
So, the probability of getting no head i.e., would be,
Step 3: Find the value of using Binomial distribution formula.
Step 4: Find the value of
Let which is not greater than or equal to .
Let which is greater than or equal to .
This means, the least possible value of is
Therefore, option(B) is the correct answer.