Answer:
Between 15.95 ounces and 16.15 ounces.
Step-by-step explanation:
We have the following value m, being the mean, sd, being the standard deviation and n, the sample size:
m = 16.05
sd = 0.1005
n = 4
We apply the formula of this case, which would be:
m + - 2 * sd / (n ^ 1/2)
In this way we create a range, replacing we have:
16.05 + 2 * 0.1005 / (4 ^ 1/2) = 16.1505
16.05 - 2 * 0.1005 / (4 ^ 1/2) = 15.9495
Which means that 95% of all samples are between 15.95 ounces and 16.15 ounces.
Make them both equal to y
y=-2x+6
2y=x+6 y=1/2x+3
These are perpendicular since ones slope is -2 and the other is the opposite, 1/2.
Answer:
The student who weighted the rock 5 times has a 95% confidence interval of (25.2, 29.1) which is guaranteed to be more wider (less precise) than the other student who weighted the rock 20 times.
Step-by-step explanation:
What is Confidence Interval?
The confidence interval represents an interval that we can guarantee that the target variable will be within this interval for a given confidence level.
The confidence interval is given by

Where
is the mean weight
is the standard deviation
is the critical value from t-table and n is the sample size.
The term
is known as margin of error.
As the sample size is decreased the corresponding margin of error increases which results in wider confidence interval which means smaller precision.
The student who weighted the rock 5 times has a 95% confidence interval of (25.2, 29.1) which is guaranteed to be more wider (less precise) than the other student who weighted the rock 20 times.
We can say with 95% confidence that the true mean weight of the rock is within the interval of (25.2, 29.1).
To solve for the total amount that Alice paid for the 3 yards cloth, multiply the cost per yard with the additional 5% to number of yards. 5% of 93 is 4.65. The total cost per yard of cloth is 97.65. Multiplying the total cost with 3 will give 292.95. Thus, Alice paid 292.95 dollars in total.