To find the standard error, divide the standard deviation by the square root of the sample size
standard deviation = 7.5
sample size = 25......sqrt 25 = 5
standard error = 7.5 / 5 = 1.5 <==
Answer: the length is 87 feet
The width is 40 feet
Step-by-step explanation:
Let L represent the length of the playing field.
Let W represent the width of the playing field.
The playing field is rectangular. The formula for determining the perimeter of a rectangle is expressed as
Perimeter = 2(L + W)
The perimeter of a playing field for a certain sport is 254 ft. This means that
254 = 2(L + W)
L + W = 254/2
L + W = 127 - - - - - - - - - - - -1
The length is 47 ft longer than the width. This means that
L = W + 47
Substituting L = W + 47 into equation 1, it becomes
W + 47 + W = 127
2W + 47 = 127
2W = 127 - 47 = 80
W = 80/2 = 40
L = W + 47 = 40 + 47
L = 87
Answer:
(-1,-7)
Step-by-step explanation:
Substitute 2x-5 (from the first equation) as the y-value for the second equation, so you have something that looks like this:
2x-5 = -2x-9
Add 2x to both sides: 4x-5 = -9
Add 5 to both sides 4x = -4
Divide both sides by 4: x = -1
Substitute -1 for x in either equation (you'll get the same y-value)
Answer:
The length of diagonal BD is 11·(1 + √3)
The length of diagonal AC = 22
Step-by-step explanation:
The given data are;
Quadrilateral ABCD = A kite
The length of segment AD = 22
The measure of ∠DAE = 60°
The measure of ∠BCEE = 45°
Whereby, triangle ΔADE = A right triangle, and DE is the perpendicular bisector of AC, by trigonometric ratio, we have;
AE = EC
DE = 22 × sin(60°) = 11·√3
AE = 22 × cos(60°) = 11
∴ AE = EC = 11
BE = EC × tan(∠BCE) = 11 × tan(45°) = 11
The length of the diagonal BD = BE + DE (By segment addition property)
∴ BD = 11 + 11·√3 = 11·(1 + √3)
The length of diagonal BD = 11·(1 + √3)
The length of diagonal AC = AE + EC
∴ AC + 11 + 11 = 22
The length of diagonal AC = 22.
