Question

Statistics students in Quebec Universities score 75.91 on average on a test of basic math

ability. The standard deviation of the test scores is 14.1415. If we choose 8 students at random and give

them the test, what is the exact probability that the mean of these 8 scores will be 70.00 or lower?

Answer #1

Solution :

Given that ,

mean = = 75.91

standard deviation = =14.1415

n=8

P(x < 70) = P[(x - ) / /n < (70-75.291) /14.1415/8 ]

= P(z < -1.06)

Using z table,

=0.1446

probability that the mean of these 8 scores will be 70.00 or lower=0.1446

Basic statistics course is offered in Harvard and Penn State
both. In a test, the average score of 50 Harvard students is 75
points and standard deviation is 10 points where as for 45 Penn
State students, these parameters are 72 points and 8 points
respectively. Construct 94% confidence interval for the difference
in the mean scores.

a
sample have 10 students
the average score in math is less than the average in
english
x1= test scores in math
x2= test scores in english
assume the scores follow normal distribution
let u1 be the population mean of math scored
let u2 be the population mean of english score
the score are given below
student. math. english
1. 18. 22
2. 22. 24
3. 19. 16
4. 23. 19
5. 20. 21
6. 18. 18
7. 16. 17...

A professor wants to know if her introductory statistics class
has a good grasp of basic
math. Six students are chosen at random from the class and given
a math proficiency
test. The six students score a sample average of 60.83 with a
sample standard deviation of 13.17. Can the professor conclude that
the mean score for the class on the test would
be below 70? Use a significance level of 0.05

The average on a statistics test was 75 with a standard
deviation of 11. If the test scores are normally distributed, find
the probability that the mean score of 36 randomly selected
students is between 72 and 81.

The
average on a statistics test was 76 with a standard deviation of
11. If the test scores are normally distributed, find the
probability that the mean score of 36 randomly selected students is
between greater than 81. *

The
average on a statistics test was 75 with a standard deviation of
11. If the test scores are normally distributed, find the
probability that the mean score of 25 randomly selected students is
between greater than 82.

For all U.S. students nationally who take the SAT, the average
SAT Math score is 500, with a population standard deviation of 125.
A random sample of 10 students entering Whitmer College had an
average SAT Math (SAT-M) score of 530. The sample data can be used
to test the claim that the mean SAT-M score of all Whitmer College
students is different than the national mean SAT-M score. Based on
the given information, have the conditions for this hypothesis...

Five years ago, the average math SAT score for students at one
school was 475. A teacher wants to perform a hypothesis test to
determine whether the mean math SAT score of students at the school
has improved. The mean math SAT score for a random sample of 40
students from this school is 469 with a standard deviation of 73.
Do the data provide sufficient evidence to conclude that the mean
math SAT score for students at the school...

Suppose the scores on a reading ability test are normally
distributed with a mean of 65 and a standard deviation of 8.
A) If one student is chosen at random, what is the probability
that the student's score is greater than 81 points"?
B) If 500 students took the reading ability test HOW MANY
students would expect to earn a score greater than 81 points?
c) Find the probability of randomly selecting 35 students (all
from the same class) that...

Do students tend to improve their SAT math score the second time
they take the test? A random sample of four students who took the
test twice provided the given scores.
Student
1
2
3
4
First Score
450
520
720
600
Second Score
440
600
720
630
Assuming that the change in SAT Math score (second score—first
score) for the population of all students taking the test twice is
Normally distributed with mean μ , are we convinced that...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 12 minutes ago

asked 12 minutes ago

asked 12 minutes ago

asked 14 minutes ago

asked 14 minutes ago

asked 18 minutes ago

asked 20 minutes ago

asked 27 minutes ago

asked 40 minutes ago

asked 55 minutes ago

asked 1 hour ago

asked 1 hour ago