Step-by-step explanation:
Mean = 81740
Standard deviation = 4590
Sample size = 15
Alpha level = 1-0.95 = 0.05
Df = 15-1 = 14
Critical value:
alpha/2 = 0.05/2 = 0.05
t0.025
t critical value = 2.145
Margin of error ME
2.145 x 4590/√15
2.145 x 4590/3.873
ME = 2542.09
Confidence interval
Lower CI = mean - ME
= 81740-2542.09
= 79197.91
Upper CI = mean + ME
= 81740+2542.09
= 84282.09
[ 79197.91, 84282.09]
B.
Using excel, exact answer for CI
Lower limit = 79198.142724212173
Upper limit = 84281.8572757827
C.
The assumptions to be made from the population are that
1. Samples are random
2. These samples are gotten from an approximately normal distribution
-10(-12+30)
-10 multiplied by 18
-180
Well, let's first find our rate of bags to meters.
If 12 bags of plaster covers 54m^2, then we need to divide 54 by 12 to figure out how many meters 1 bag of plaster covers. We will then use that rate and divide 36 by it in order to solve for how many bags of plaster is required.
54 / 12 = 4.5.
This means each bag of plaster covers 4.5m^2.
Divide 36 by 4.5;
36 / 4.5 = 8.
This means that we will need 8 bags of plaster to cover 36m^2.
I hope this helps!
Answer:
it sideways
Step-by-step explanation: