Question

8 coins are tossed simultaneously. The probability of getting

at least 6 heads is

• A. $\frac { 57 } { 64 }$
• B. $\frac { 229 } { 256 }$
• C. $\frac { 7 } { 64 }$
• D. $\frac { 37 } { 256 }$

Answer 1

Answer: (D)

$\frac { 37 } { 256 }$

Answer 2

The required probability

$= { } ^ { 8 } C _ { 6 } \left( \frac { 1 } { 2 } \right) ^ { 6 } \cdot \left( \frac { 1 } { 2 } \right) ^ { 2 } + { } ^ { 8 } C _ { 7 } \left( \frac { 1 } { 2 } \right) ^ { 7 } \cdot \left( \frac { 1 } { 2 } \right) + { } ^ { 8 } C _ { 8 } \left( \frac { 1 } { 2 } \right) ^ { 8 } = \frac { 37 } { 256 }$.