-1/3+2z=-5/6
-2/6+2z=-5/6
Add 2/6 to both sides:
2z=-3/6
2z=-1/2
Divide both sides by 2
z=-1/4
Hope this helps :)
The range is (10,11.5,12.5,13.75)
Enjoy your day, mi amor! ❤️
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 
y/x = k
6.4/4 = 1.6
11.2 / 7 =1.6
16/10 = 1.6
20.8 /13 =1.6
This is a direct variation and the constant is 1.6
y=1.6x
1. B 2. A 3. B that’s what you looking for