`8` coins are tossed simultaneously. The probability of getting at least 6 heads is

Options

A. `(7)/(64)`
B. `(57)/(64)`
C. `(37)/(256)`
D. `(229)/(256)`

Answer

C

Explanation

In tossing of coin getting r head out of n tossing ` = ""^(n)C_(r).((1)/(2))^(n)`.
`therefore` Required probability .
`= (""^(6)C_(6)+ ""^(8)C_(7) +""^(8)C_(8))((1)/(2))^(8)`.
` = (28 + 8 + 1) xx (1)/(256) = (37)/(256)`