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Answer:
Step-by-step explanation:
Rewrite this as
Knowing that i-squared = -1:
Both i-squared and 100 are perfect squares, so this simplifies to
±10i
Answer:
2 one and the 4 one
Step-by-step explanation:
Answer:
Yes, we can conclude that the population standard deviation of TV watching times for teenagers is less than 2.66
Step-by-step explanation:
H0 : σ² = 2.66²
H1 : σ² < 2.66²
X²c = (n - 1)*s² ÷ σ²
sample size, n = 40
Sample standard deviation, s = 1.9
X²c = ((40 - 1) * 1.9²) ÷ 2.66²
X²c = 140.79 ÷ 7.0756
X²c = 19.897
Using a confidence level of 95%
Degree of freedom, df = n - 1 ; df = 40 - 1 = 39
The critical value using the chi distribution table is 25.6954
Comparing the test statistic with the critical value :
19.897 < 25.6954
Test statistic < Critical value ; Reject the Null
Hence, we can conclude that the population standard deviation of TV watching times for teenagers is less than 2.66
