Note :- If sample size n > 30 OR Population standard deviation σ is given then We use Z test.
If sample size n < 30 AND Population standard deviation σ is unknown then we use t test.
In this question we are not given Population standard deviations σ1 and σ2.
Also n1 = 14 and n2 = 13 both sample sizes are LESS than 30.
Therefore we use t test.
Given :- Assume the population standard deviations are equal. ( σ1 = σ2)
then Degrees of freedom = n1 + n2 - 2 = 14 + 13 - 2 = 25.
(kindly find the image attached with this solution)
Answer :- Therefore 25 degrees of freedom are used to find the t critical value.
Answer:
sphere volume = 3052.1 in³
Step-by-step explanation:
sphere volume = 4/3πr³ = 4/3(3.14)(9³) = 3052.1 in³
Answer:
40
Step-by-step explanation:
(2/5)*n - 6 = 10 Add 6 to both sides
(2/5)*n - 6 + 6 = 10 + 6 Combine
(2/5)*n = 16 Multiply both sides by 5/2
(5/2)(2/5)n = 16*(5/2)
n = 80 / 2
n = 40
The correct answer is 3x = 42
There would be a total of 42/3 or 14 packages.