Answer:
31
Step-by-step explanation:
Given:
n = 20, sample size
xbar = 17.5, sample mean
s = 3.8, sample standard deiation
99% confidence interval
The degrees of freedom is
df = n-1 = 19
We do not know the population standard deviation, so we should determine t* that corresponds to df = 19.
From a one-tailed distribution, 99% CI means using a p-value of 0.005.
Obtain
t* = 2.8609.
The 99% confidence interval is
xbar +/- t*(s/√n)
t*(s/√n) = 2.8609*(3.8/√20) = 2.4309
The 99% confidence interval is
(17.5 - 2.4309, 17.5 + 2.4309) = (15.069, 19.931)
Answer: The 99% confidence interval is (15.07, 19.93)
Answer:
I. Length, L = 9.552 meters
II. Width, W = 7.96 meters
Step-by-step explanation:
Let the length = L
Let the width = W
Given the following data;
Perimeter = 35 m
Translating the word problem into an algebraic equation, we have;
Length = 1.2W
To find the dimension of the room;
The perimeter of a rectangle is given by the formula;
P = 2(L + W)
Substituting into the formula, we have;
35 = 2(1.2W + W)
35 = 2(2.2W)
35 = 4.4W
Width, W = 7.96 meters
Next, we would find the length of the rectangle;
L = 1.2*W
L = 1.2 * 7.96
Length, L = 9.552 meters
19. The balloon hits the ground means -16t2+25t+3=0
After you solve the equation, there are 2 solution ~1.67 or ~-0.11 (the time can not be negative) so the solution is 1.67s
20.substitute t=1 to the function -16(1)2+25(1)+3=-16+25+3=12 ft. So the height is 12ft when t=1