The binomial distribution Quiz

1. $X\sim\mathrm{B}(10,0.2)$. Find $\mathrm{P}(X=2)$.

• A. $0.302$
• B. $0.678$
• C. $0.200$
• D. $0.045$

2. $X\sim\mathrm{B}(8,0.4)$. Find $\mathrm{P}(X\ge5)$.

• A. $0.826$
• B. $0.594$
• C. $0.174$
• D. $0.635$

3. $X\sim\mathrm{B}(10,0.7)$. Find $\mathrm{P}(X\le4)$.

• A. $0.953$
• B. $0.150$
• C. $0.200$
• D. $0.0473$

4. $X\sim\mathrm{B}(n,p)$ has mean $12$ and variance $7.2$. Find $n$.

• A. $20$
• B. $30$
• C. $40$
• D. $60$

5. Which is a reason a binomial model may not be suitable?

• A. The probability of success changes from trial to trial
• B. Each trial has two outcomes
• C. The number of trials is fixed
• D. Trials are independent