Answer: 0.2857
<u>Step-by-step explanation:</u>
At least one teacher means exactly 1 or exactly 2 or exactly 3 teachers. Find the probability of each and add them up.

One teacher + Two teachers + Three teachers = 0.2857
Answer:


The confidence interval of standard deviation is:
to 
Step-by-step explanation:
Given

See attachment for the formatted data
Solving (a): The mean
This is calculated as:

So, we have:




Solving (b): The standard deviation
This is calculated as:




--- approximated
Solving (c): 95% confidence interval of standard deviation
We have:

So:



Calculate the degree of freedom (df)



Determine the critical value at row
and columns
and 
So, we have:
---- at 
--- at 
So, the confidence interval of the standard deviation is:
to 
to 
to 
to 
Answer:
Speed of a= 21 miles/hr
r = Speed of b= 7 miles/hr
Speed of a = 3r
Step-by-step explanation:
The cyclist are 112 miles apart
Time traveled by two = 4 hours
Speed of a = 3 * speed of b
If a cylcles 3 times More than b, then a will cover 3*distance of b
But speed = distance/time
Time = 4hours
Total distance=112
a = 3b
3b + b = 112
4b = 112
b = 112/4
b = 28 miles
a = 3b
a = 3*28
a = 84 Miles
They bought traveled 4 hours
Speed of a = 84miles/4 hours
Speed of a= 21 miles/hr
Speed of b = 28miles/4 hours
Speed of b = 7 miles/hr
The area of the kite is 2.25 square feet
<h3>How to determine the area of the kite?</h3>
The area of the kite is calculated using:
Area = 0.5 * pq
Where p and q are the diagonals of the kite.
In this figure,
p = 3
q = 0.75 * 2 = 1.5
So, we have:
Area = 0.5 * 3 * 1.5
Evaluate
Area = 2.25
Hence, the area of the kite is 2.25
Read more about areas at:
brainly.com/question/24487155
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