Answer:
We reject the null hypothesis and fail to accept it and update that estimate that typical teenager sent does not 67 text messages per day.
Step-by-step explanation:
We are given the sample:
51, 175, 47, 49, 44, 54, 145, 203, 21, 59, 42, 100
Formula:
where are data points,
is the mean and n is the number of observations.
Sum of squares of differences = 992.25 + 8556.25 + 1260.25 + 1122.25 + 1482.25 + 812.25 + 3906.25 + 14520.25 + 3782.25 + 552.25 + 1640.25 + 306.25 = 3539.363636
We are given the following in the question:
Population mean, μ =67
Sample mean, = 82.5
Sample size, n = 12
Alpha, α = 0.05
Sample standard deviation, s = 59.5
First, we design the null and the alternate hypothesis
We use One-tailed t test to perform this hypothesis.
b) Formula:
Putting all the values, we have
Now,
a) Since,
We reject the null hypothesis and fail to accept it and update that estimate that typical teenager send more than 67 text messages per day.