Answer:
The variance for the number of correct answers is 2.8 questions
Step-by-step explanation:
The number of correct answers follows binomial distribution, in which we have:
- n identical and independents events: the 15 questions
- two possibles results that we call success and fail: The answer is correct and the answer is incorrect
- probability p of success and 1-p of fail. Probability 1/4 of get the answer correct and probability of 3/4 of get the answer incorrect. This probabilities are calculated on that way because every question have 4 possible answers and one of which is correct.
So, the variance for a variable x that follows a Binomial distributions is:
V(x)=n*p*(1-p)
Then, the variance for the number of correct answers is:
V(x)=15*(1/4)*(3/4) = 2.8125 ≈ 2.8
Because n is equal to 15, p is equal to 1/4 and (1-p) is equal to 3/4.
Answer:
I don't know sorry for that I tried my best
Answer: Annie will have to make 228 cookies
explanation:
let y represent the total number cookies that Annie will make.
<h3>y= 342*(2/3)</h3><h3>y=228</h3><h3 /><h3 />