Answer:
a) (76.21,83.79)
b) (77.32,82.68)
c) Interval decreases
Step-by-step explanation:
We are given the following information in the question:
Sample size, n = 60
Sample mean = 80
Sample standard Deviation, s = 15
a) 95% Confidence interval:

Putting the values, we get,


b) Sample size, n = 120
95% Confidence interval:

c) As observed increasing the sample size, the confidence interval become smaller.
28.55 mph
hope i helped you :3
Plus all the sides that simple if area of triangle is 1/2 x b x h
Answer:
yup
Step-by-step explanation:
Answer:
A triangle is a total of 180 degrees
So to find what x equals we are going to add up all the degree measurements and make them equal to 180
3x+2x+20+4x-20=180 (combine any like terms on the left)
3x+2x+4x+20-20=180 (3x+2x+4x=9x, 20-20=0)
9x=180 (divide both sides by 9)
x=20
Hope this helps ;)
Step-by-step explanation: