Answer:
a. E(x) = 3.730
b. c = 3.8475
c. 0.4308
Step-by-step explanation:
a.
Given
0 x < 3
F(x) = (x-3)/1.13, 3 < x < 4.13
1 x > 4.13
Calculating E(x)
First, we'll calculate the pdf, f(x).
f(x) is the derivative of F(x)
So, if F(x) = (x-3)/1.13
f(x) = F'(x) = 1/1.13, 3 < x < 4.13
E(x) is the integral of xf(x)
xf(x) = x * 1/1.3 = x/1.3
Integrating x/1.3
E(x) = x²/(2*1.13)
E(x) = x²/2.26 , 3 < x < 4.13
E(x) = (4.13²-3²)/2.16
E(x) = 3.730046296296296
E(x) = 3.730 (approximated)
b.
What is the value c such that P(X < c) = 0.75
First, we'll solve F(c)
F(c) = P(x<c)
F(c) = (c-3)/1.13= 0.75
c - 3 = 1.13 * 0.75
c - 3 = 0.8475
c = 3 + 0.8475
c = 3.8475
c.
What is the probability that X falls within 0.28 minutes of its mean?
Here we'll solve for
P(3.73 - 0.28 < X < 3.73 + 0.28)
= F(3.73 + 0.28) - F(3.73 + 0.28)
= 2*0.28/1.3 = 0.430769
= 0.4308 -- Approximated
Given:
- the perimeter of a rectangular field is 84 yards
- the ratio of the length to the width is 2:1
To find:
- the length
- the width
- the area
Answer:
Let's assume that the length is 2x and the width is 1x.
We know that the formula to find the perimeter of a rectangle is as follows:
Perimeter = 2 × (Length + Width)
Substituting the values that we have, into the formula above,
84 = 2 × (2x + 1x)
84 = 2 × 3x
84/2 = 3x
42 = 3x
x = 42/3
x = 14
Since we know the value of 'x', let's use it to find the length and the width.
Length = 2x = 2 × 14 = 28
Width = 1x = 1 × 14 = 14
Since we now know the length and the width, let's find the area of the rectangle.
The formula to find the area of a rectangle:
Area = Length × Width
Substituting the values we have into the formula,
Area = 28 × 14
Area = 392
Therefore, the area of the rectangle is 392 square yards.
Hope it helps. :)
25% is equal to
. To get 25% of 300, we multiply 300 by either 0.25 or
. This gives us
