Answer:
A 90% confidence interval for the mean number of letter sounds identified in one minute is: (30.84, 37.34).
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
That is z with a pvalue of 
, so Z = 1.645.
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 34.09 - 3.25 = 30.84.
The upper end of the interval is the sample mean added to M. So it is 34.09 + 3.25 = 37.34.
A 90% confidence interval for the mean number of letter sounds identified in one minute is: (30.84, 37.34).
Answer:
For #3 the answer is 113.04 (6 + g) / 32
Step-by-step explanation:
A = Pi * r * (r + g)
12/2 = 6 ft
A = 3.14 * (6) * (6 + g) = 113.04 (6 + g) square feet
113.04 (6 + g) / 32
Answer:
178
Step-by-step explanation:
Use Pythagorean Theorem to find the Hypotenuse
30^2+72^2=78^2
Use perimeter formula
a+b+c
38+72+30
Answer:
y = - 
x + 10
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mc + c ( m is the slope and c the y- intercept )
Here m = - and crosses the y- axis at (0, 10 ) ⇒ c = 10
y = - x + 10 ← equation of line
Answer: 15%
Step-by-step explanation:
The Percentage decrease will be:
= Decrease in weight / Old weight × 100
= (200 - 170) / 200 × 100
= 30/200 × 100
= 15%
The Percentage decrease is 15%
