Let
n = number of data
s = standard deviation (sample)
S = standard deviation (population)
The working equations is

To find

, : (1 - 0.90)/2 = 0.05
To find

, : 1 - 0.05 = 0.95
Degrees of freedom = n-1 = 24 - 1 = 23
This is shown in the figure attached. Since there is no row for df=23, we interpolate. Thus,
Substitute all values,

Thus the answer is,
Answer:
1. -3
2. 7
3. -2
4. 3
Step-by-step explanation:
1. idk
2. 3.2 move 3b over to get 3.2-3b-4.7=-3.3 move 4.7 over to get
3.2b-3b=4.7-3.3 now 3.2b-3b=.2b and 4.7-3.3=1.4 .2b/.2=b 1.4/.2=7 so b=7
3. 4.6y-y+4=y-1.2 now switch the 4 and the y to read 4.6y-2y=-4-1.2
2.6y=-5.2 divide both sides by 2.6 to get y=-2
4. 7.5c-2.5c+8=-7 move 8 to other side to get 7.5c-2.5c=-8-7
5c=-15 divide both sides by 5 getting c=3
Answer:
The mean is 15
Explanation:
The x value that would get a median of 12 is three, which when taken the mean of the numbers when x is three, you get 15