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
Answer:
2070 inches
Step-by-step explanation:
V = W x L x D
= 18 x 10 x 11.5 = 2070 inches
Answer:
9 bags
Step-by-step explanation:
First we will need to calculate the area of their entire backyard, which has a shape of trapezium.
So the formula for the area of a trapezium is 
a and b are the lenghts of the parallel sides and h is the height.
From the picture 
Then we plug into our formula
square feet
To get the number of bags required we just simply divide the aree of their entire yard by the space that 1 bag covers. We get:
bags
This is more than 8 bags so they will need 9 bags to cover their entire yard.
it's irrational
A rational number can be put over a fraction, while this number continues forever
