Answer:
5 + 8 - 6
Step-by-step explanation:
or if you want a solved answer its 7.
Find common denominators and move from there
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.
To find the residual I would subtract the predicted value from the measured value so for x-value 1 the residual would be 2-2.6 = -0.6
Answer is A and C
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