Answer:
8.2+/-0.25
= ( 7.95, 8.45) years
the 95% confidence interval (a,b) = (7.95, 8.45) years
Step-by-step explanation:
Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.
The confidence interval of a statistical data can be written as.
x+/-zr/√n
Given that;
Mean x = 8.2 years
Standard deviation r = 1.1 years
Number of samples n = 75
Confidence interval = 95%
z value(at 95% confidence) = 1.96
Substituting the values we have;
8.2+/-1.96(1.1/√75)
8.2+/-1.96(0.127017059221)
8.2+/-0.248953436074
8.2+/-0.25
= ( 7.95, 8.45)
Therefore the 95% confidence interval (a,b) = (7.95, 8.45) years
Use compound interest formula:
Future value, F
25000=P(1+i)^n
where
P=present value to be found
i=annual interest rate = 0.065
n=number of years = 6
so
25000=P(1.065)^6
=>
P=(25000/1.065^6)=$17133.353
Let vons market receive x loaves. Then savemart received x+12 loaves and Ralphs received x + 12 + 6 = x + 18 loaves, Therefore:-
x + x + 12 + x + 18 = 180
3x + 30 = 180
3x = 150
x = 150/3 = 50
So vons received 50, savemart received 62 and ralph's received 68 loves. Answer
