Answer: 0.86 of the exam scores are between 68 and 77.99 points
Step-by-step explanation:
Since the set of computer science exam scores are normally distributed, we would apply the formula for normal distribution which is expressed as
z = (x - µ)/σ
Where
x = computer science exam scores .
µ = mean score
σ = standard deviation
From the information given,
µ = 71.33 points
σ = 3 points
We want to find the proportion of the exam scores are between 68 and 77.99 points. It is expressed as
P(68 ≤ x ≤ 77.99)
For x = 68,
z = (68 - 71.33)/3 = - 1.11
Looking at the normal distribution table, the probability corresponding to the z score is 0.13
For x = 68,
z = (77.99 - 71.33)/3 = 2.22
Looking at the normal distribution table, the probability corresponding to the z score is 0.99
P(68 ≤ x ≤ 77.99) = 0.99 - 0.13 = 0.86
3/9 is your answer. 3+6=9 and there are 3 red marbles.
This Question is Incomplete
Complete Question
As an aid to the establishment of personnel requirements, the director of a hospital wishes to estimate the mean number of people who are admitted to the emergency room during a 24-hour period. The director randomly selects 64 different 24-hour periods and determines the number of admissions for each. For this sample, X = 396 and S = 100. Using the sample standard deviation as an estimate for the population standard deviation, what size sample should the director choose if she wishes to estimate the mean number of admissions per 24-hour period to within 1 admission with 99% reliability, what size sample should she choose?
Answer:
Sample size n = 16
Step-by-step explanation:
We use the formula for Margin of Error for the question
Margin of Error = z × Standard deviation/√n
Margin of Error = 1
z score for 99% confidence interval = 2.576
Standard deviation = 100
1 = 2.576 × 100/√n
1 × √n = 257.6
√n = 257.6/1
n = √257.6
n = 16.049922118
Approximately = 16
Therefore, the sample size = 16
Answer:
-10 and 5
Step-by-step explanation:
because -10 x 5 = -50 and -10 + 5 = -5!
Where is the shaded region?
