The lengths of text messages are normally distributed with a population standard deviation of 6 characters and an unknown population mean. If a random sample of 27 text messages is taken and results in a sample mean of 29 characters, find a 95% confidence interval for the population mean. Round your answers to two decimal places.

29+/-2.26

= (26.74, 31.26) characters

Therefore the 95% confidence interval (a,b) = (26.74, 31.26) characters

Step-by-step explanation:

Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.

The confidence interval of a statistical data can be written as.

x+/-zr/√n

Given that;

Mean x = 29 characters

Standard deviation r = 6 characters

Number of samples n = 27

Confidence level = 95%

z value(at 95% confidence) = 1.96

Substituting the values we have;

29+/-1.96(6/√27)

29+/-1.96(1.154700538379)

29+/-2.263213055223

29+/-2.26

= (26.74, 31.26) characters

Therefore the 95% confidence interval (a,b) = (26.74, 31.26) characters

answer: a. 13/44

step-by-step explanation: judging by the information given to us, we are looking for experimental probability. we can see that 13 males have chosen chocolate ice cream. there are 44 ice creams in total (remember that the total is always the denominator). so our answer is 13/44.