a)
= 4*0.18 +......+0*0.07
, = 2.45
=1.2075
therefore ,
b) The sampling distribution of sample mean,
follow normal distribution
with mean ,
(population mean )
and standard deviation of
, known as standard error ,
= 0.1554
where
is the population standard deviation and n is the sample size
.
c)
with mean = 2.45 and standard error = 0.1554
then
= 0.0002
5. North Carolina State University posts the complete grade distributions for its courses online. The distribution of grades for all students in all sections of Accounting 210 in the spring semester...
3. Exam grades across all students across all sections of an introductory statistics class are approximately normally distributed with a mean of 72 and a standard deviation of 11. Use the normal distribution to find answer the following questions. a. What percent of students scored above a 90%? b. What percent scored below 60%? c. If the lowest 5% of students will be required to attend an extra study session, what grade is the cutoff for being required to attend...
The professor of a
introductory calculus class has stated that, historically, the
distribution of final exam grades in the course resemble a Normal
distribution with a mean final exam mark of μ=63μ=63% and a
standard deviation of σ=9σ=9%.
If using/finding zz-values, use three decimals.
(a) What is the probability that a random chosen
final exam mark in this course will be at least 73%? Answer to four
decimals.
(b) In order to pass this course, a student must
have a...
It is known that time spent partying per month by Kent State students is normal with a mean of 46 hrs and standard deviation of 4 hrs. What is the probability that a randomly chosen Kent State student spends more than 49 hours partying per month? 1. 0 2. 0.0668 3. 0.8535 What is the probability that a randomly selected Kent State student spends less that 40 hours partying per month? 4. 0.2266 For which one of the following sets...
TEST 1: ANSWERS INTS EACH). This section takes around 5 minutes. Name Spring 2019 8) A researcher wants to determine whether female teachers give higher or lower grades, on average, then male teachers. She picks a random sample by picking a random sample of schools, in the schools picked, picking a random sample of departments, and in the departments picked, picking a random sample of teachers. What kind of sampling was performed? d) voluntary response e) cluster b) stratified Random...
i need help on question 3 to 22 please.
Midterm ex review. MATH 101 Use the following information to answer the next four exercises. The midterm grades on a chemistry exam, graded on a scale of 0 to 100, were: 62, 64, 65, 65, 68, 70, 72, 72, 74, 75, 75, 75, 76,78, 78, 81, 82, 83, 84, 85, 87, 88, 92, 95, 98, 98, 100, 100,740 1. Do you see any outliers in this data? If so, how would...