The answer is c
hope that helps :)))
The answer to your question is 20
Answer:
Emily: 13, Peter: 9, Joshua: 18
Step-by-step explanation:
Emily = x
Peter = Emily - 4 = x - 4
Joshua = 2(Peter) = 2(x - 4)
Total = 40 = Emily + Peter + Joshua = (x) + (x - 4) + 2(x - 4)
40 = 2x - 4 + 2x -8
40 = 4x - 4 - 8
40 = 4x - 12
52 = 4x
x = 13
Emily = 13
Peter = 13 - 4 = 9
Joshua = 2(13 - 4) = 2(9) = 18
13 + 9 +18 = 40
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