Answer: 95% confidence interval = 20,000 ± 2.12
( 19228.736 , 20771.263 ) OR ( 19229 , 20771 )
Step-by-step explanation:
Given :
Sample size(n) = 17
Sample mean = 20000
Sample standard deviation = 1,500
5% confidence
∴ = 0.025
Degree of freedom () = n-1 = 16
∵ Critical value at ( 0.025 , 16 ) = 2.12
∴ 95% confidence interval = mean ±
Critical value at 95% confidence interval = 20,000 ± 2.12
( 19228.736 , 20771.263 ) OR ( 19229 , 20771 )
ANSWER
Find out the how long will the Yellow balloon be higher than the orange balloon.
To proof
Now the diagram is given below
As given
A yellow hot-air balloon is 100 feet off the ground and rising at rate of 8 feet per second.
i.e height of the yellow baloon off the ground = 100 feet
rising at rate = 8 feet per second.
.An orange hot-air balloon is 160 feet off the ground and rising at a rate of 5 feet per second.
i.e height of the orange baloon off the ground = 160 feet
rising at rate = 5feet per second.
Formula
Relative velocity = rising rate of yellow balloon - rising rate of orange balloon
= 8 -5
= 3 feet per second
Relative distance = height of the yellow baloon off the ground - height of the orange baloon off the ground
= 160 -100
= 60 feet
put in the formula
= 20 second
after 20 second Yellow balloon will be higher than the orange balloon.
Hence proved
