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:
The length of the square is 6 units.
Step-by-step explanation:
Given that all sides of the square are the same and the area of square formula is A = length×breadth. So let's make x as the sides :
No. which have factors 2 & 5 have 2 & 5 as their prime factor
therefore, No. are :
2*5 = 10
2*5*2 = 20
2*5*3 = 30
Answer:
D
Step-by-step explanation:
I just did this test and D was the right answer.
5k-4k=-1+-1
k=-2, its all aboit rearranging the order of numders based on there like terms. If you need any more help ask.
