Question

The probability of happening of an event in a trial is $0.5$. The probability of happening of the event atleast once if the experiment is repeated $3$ times is

• A. $1.589$
• B. $0.567$
• C. $0.875$
• D. $1.9275$

Answer 1

The correct option is C $0.875$

Probability of happening of an event in a trail $=0.5$

Probability of not happening an event in a trial $=1-0.5=0.5$

Probability of happening of the event at least once is 1-(probability of not happening an event )

$1-\left(0.5\right)\left(0.5\right)\left(0.5\right)$

$1-0.125=0.875$

$\therefore$ Probability of happening of the event at least once = $0.875$