0.63 is the correct answer
Answer:
a) p=0.2
b) probability of passing is 0.01696
.
c) The expected value of correct questions is 1.2
Step-by-step explanation:
a) Since each question has 5 options, all of them equally likely, and only one correct answer, then the probability of having a correct answer is 1/5 = 0.2.
b) Let X be the number of correct answers. We will model this situation by considering X as a binomial random variable with a success probability of p=0.2 and having n=6 samples. We have the following for k=0,1,2,3,4,5,6
.
Recall that
In this case, the student passes if X is at least four correct questions, then

c)The expected value of a binomial random variable with parameters n and p is
. IN our case, n=6 and p =0.2. Then the expected value of correct answers is 
Answer:Combine like terms
3
+
5
−
=
9
−
7
+
1
2
{\color{#c92786}{3x}}+5{\color{#c92786}{-x}}=9x-7+12
3x+5−x=9x−7+12
2
+
5
=
9
−
7
+
1
2
{\color{#c92786}{2x}}+5=9x-7+12
2x+5=9x−7+12
2
Add the numbers
3
Subtract the same term from both sides of the equation
4
Simplify
5
Subtract the same term from both sides of the equation
6
Simplify
7
Divide both sides of the equation by the same term
8
Simplify
HOPE THIS HELPS :)
Step-by-step explanation:
Answer:
a.) 9, -9
b.) 2(sqrt)15, -2(sqrt)15
c.) 4, -2+2i(sqrt)3, -2-2i(sqrt)3
d.) 3(sqrt)75
(some of the numbers are placed differently than I wrote them so here are screenshots- pls look at them rather than what I wrote ;w;)