Question

Probability that a person will develop immunity after vaccination is $0.8$. If $8$ people are given the vaccine then probability that all develop immunity is $=$

• A. $(0.2{)}^8$
• B. $(0.8{)}^8$
• C. $1$
• D. ${}^8{C}_6\left(0.2{)}^6\right(0.8{)}^2$

Answer 1

The correct option is B $(0.8{)}^8$

Probability that a person develops immunity after vaccination is $0.8$

$8$ people are given vaccine

Probability of developing immunity after vaccination of two people will be $0.8\times 0.8$

Probability that all develop immunity after vaccination will be $0.8\times 0.8\times 0.8.....\times 0.8=(0.8{)}^8$

Hence, the answer is $(0.8{)}^8$