A teacher administers a standardized math test to his class of 75 students. The mean score (out of 300 possible points) is 235. From previous studies, you know the population standard deviation is 28. Using the sample data given, calculate a 95% confidence interval for the population mean.

(228.663 ; 241.337)

Step-by-step explanation:

Given that:

Mean (m) = 235

Standard deviation (s) = 28

α = 95%

Zcritical at 95% = 1.96

Sample size (n) = 75

The confidence interval of the population mean can be obtained using the relation :

Mean ± Error

Error = Zcritical * (s/sqrt(n))

Error = 1.96 * (28/sqrt(75))

Error = 1.96 * 3.2331615

Error = 6.33699654

Error = 6.337

Lower boundary = 235 - 6.337 = 228.663

Upper boundary = 235 + 6.337 = 241.337

(228.663 ; 241.337)

yes

step-by-step explanation:

give me the question

\

from the figure we get,

the x axis shows   the months and,

the y-axis shows the number of satisfied customer.

each line or each cell in upward direction (y-axis) shows 500.

the appropriate scale for the y - axis is: -

a = 2000 customers

b = 4000 customers

c = 6000 customers

d = 8000 customers

e = 10000 customers

f = 12000 customers

g = 14000 customers