Answer:
21
Step-by-step explanation:
Box Plot has less variability in the data. We can determine this by the distances between the beginning of the data to the end (range) and the distances between lower quartile and the upper quartile (interquartile range).
Box #1
Range - 30
IQR - 15
Box #2
Range - approximately 23
IQR - approximately 9
Box #2 has less variation in the data because the distances between these 2 ranges are smaller meaning the data is closer together.
Answer:
We accept H₀ . We don´t have enough evidence to express the publisher claim is not true
Step by Step explanation:
We must evaluate if the mean of the price of college textbooks is different from the value claimed by the publisher
n < 30 then we must use t - distrbution
degree of freedom n - 1 df = 22 - 1 df = 21
As the question mentions " different " that means, a two-tail test
At 0,01 significance level α = 0,01 α/2 = 0,005
and t(c) = 2,831
Test Hypothesis
Null Hypothesis H₀ μ = μ₀
Alternative hypothesis Hₐ μ ≠ μ₀
To calculate t(s)
t(s) = ( μ - μ₀ ) /σ/√n
t(s) = ( 433,50 - 385 ) / 86,92 / √22
t(s) = 2,6171
Comparing t(c) and t(s)
t(s) < t(c)
Then t(s) is in the acceptance region we accept H₀. We don´t have enough evidence to claim that mean price differs from publisher claim