An experiment succeeds twice as often as it fails. Find the probability that in the next six trials, there will be atleast 4 successes.

Explanation

The probability of success is twice the probability of failure

Let the probability of failure be `x`

`therefore` probability of success `=2x`

`x+2 x=1`

` Rightarrow 3 x=1 `

`Rightarrow x=frac{1}{3}`

` therefore 2 x=frac{2}{3} `

Let `p=frac{1}{3} and q=frac{2}{3}`

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