Answer:
The correct answer is option 'a' : 120 is more than 2.5 standard deviations above the expected value.
Step-by-step explanation:
For an exponential distribution we have
The expected value μ = 80
No of trails n = 200
Thus we have

The deviation is related to expected value and probability as

Thus the values between the given deviation is

Now since 120 successes are out of the range of [62.75,97.25] thus 120 is more than the expected value.
Answer:
Step-by-step explanation:
y= -(1/2)x - 5
60 divided by 0.4(40%)=150
=150
Answer and Step-by-step explanation:
The computation is shown below:
Let us assume that
Spam Email be S
And, test spam positive be T
Given that
P(S) = 0.3


Now based on the above information, the probabilities are as follows
i. P(Spam Email) is
= P(S)
= 0.3

= 1 - 0.3
= 0.7
ii. 


= 0.8906
iii. 


= 0.0221
We simply applied the above formulas so that the each part could come
Step-by-step explanation:
You're asking why

let's transpose the first equation for y
-2x-6y=18
-6y=18+2x
6y=-18-2x
y=-18/6-2x/6
y=-3-⅓x as required