You do 27x27 and get 729 is going to be your answer
Answer: The number of first-year residents she must survey to be 95% confident= 263
Step-by-step explanation:
When population standard deviation (
) is known and margin of error(E) is given, then the minimum sample size (n) is given by :-
, z* = Two-tailed critical value for the given confidence interval.
For 95% confidence level , z* = 1.96
As,
= 8.265, E = 1
So, ![n= (\dfrac{1.96\times8.265}{1})^2 =(16.1994)^2\\\\= 262.42056036\approx263\ \ \ [\text{Rounded to the next integer}]](https://tex.z-dn.net/?f=n%3D%20%28%5Cdfrac%7B1.96%5Ctimes8.265%7D%7B1%7D%29%5E2%20%3D%2816.1994%29%5E2%5C%5C%5C%5C%3D%20262.42056036%5Capprox263%5C%20%5C%20%5C%20%5B%5Ctext%7BRounded%20to%20the%20next%20integer%7D%5D)
Hence, the number of first-year residents she must survey to be 95% confident= 263
Answer:
Step-by-step explanation:
Let the other side of the rectangle be y. The perimeter of the rectangle is expressed as P = 2(x+y)
Given P = 30ft, on substituting P = 30 into the expression;
30 = 2(x+y)
x+y = 15
y = 15-x
Also since the area of the rectangle is xy;
A = xy
Substitute y = 15-x into the area;
A = x(15-x)
A = 15x-x²
The function that models its area A in terms of the length x of one of its sides is A = 15x-x²
The side of length x yields the greatest area when dA/dx = 0
dA/dx = 15-2x
15-2x = 0
-2x = -15
x = -15/-2
x = 7.5 ft
Hence the side length, x that yields the greatest area is 7.5ft.
Since y = 15-x
y = 15-7.5
y = 7.5
Area of the rectangle = 7.5*7.5
Area of the rectangle = 56.25ft²
Start by factoring an x term out of the equation:
x(x-11)=0
Now, you can set each term equal to zero and solve for x:
x=0
x-11=0
x=11
x={0, 11}
Hope this helps!!