Answer:
2.42
Step-by-step explanation:
standard deviation= sqrt(variance)
Variance=E[X2] - E[X]2
E[X] = sum(X)/n=35/9, so E[X]2 = 1225/81
E[X2] =sum(X2)/n = 189/9 = 170/81
Variance= 476/81
Standard deviation = sqrt(476/81) ~2.42
Answer:
The third option
Step-by-step explanation:
This is because you multiply the variable cost (9), by the amount they make, which is x.
Answer:
$301 - $397
Step-by-step explanation:
Using the Empirical rule
1) 68% of data falls within 1 standard deviation from the mean - that means between μ - σ and μ + σ .
2)95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ .
3)99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ .
From the above question,
Mean = 349 , standard deviation = 24.
Confidence interval = 95%
Using 2)95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ .
μ – 2σ
= 349 - 2(24)
= 349 - 48
= 301
μ + 2σ
349 + 2(24)
= 349 + 48
= 397
Therefore, according to the standard deviation rule, approximately 95% of the students spent between $301 and $397 on textbooks in a semester.
(10,5) would make the equation correct
Answer: (2, 18)
Step-by-step explanation:
When x=2, 
.
So, it should pass through (2, 18).
