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:
y = 8 degrees
Step-by-step explanation:
128 + 7y - 4 = 180
7y - 4 = 52
7y + 56
y = 8
Answer:
10.9361
Step-by-step explanation:
The lower control limit for xbar chart is
xdoublebar-A2(Rbar)
We are given that A2=0.308.
xdoublebar=sumxbar/k
Rbar=sumR/k
xbar R
5.8 0.42
6.1 0.38
16.02 0.08
15.95 0.15
16.12 0.42
6.18 0.23
5.87 0.36
16.2 0.4
Xdoublebar=(5.8+6.1+16.02+15.95+16.12+6.18+5.87+16.2)/8
Xdoublebar=88.24/8
Xdoublebar=11.03
Rbar=(0.42+0.38+0.08+0.15+0.42+0.23+0.36+0.4)/8
Rbar=2.44/8
Rbar=0.305
The lower control limit for the x-bar chart is
LCL=xdoublebar-A2(Rbar)
LCL=11.03-0.308*0.305
LCL=11.03-0.0939
LCL=10.9361
V = L * W * H
V = 4 * 4 * 8
V = 16 * 8
V = 128 cubic ft
Answer:
4.44 infinet
Step-by-step explanation:
