Circumference of a circle - derivation
This page describes how to derive the formula for the circumference of a circle.
Recall that the definition of pi (π) is the circumference c of any circle divided by its diameter d. Put as an equation, pi is defined as
π
=
c
d
Rearranging this to solve for c we get
c
=
π
d
The diameter of a circle is twice its radius, so substituting 2r for d
c
=
2
π
r
If you know the area
Recall that the area of a circle is given by
area
=
π
r
2
Solving this for r
r
2
=
a
π
So
r
=
√
a
π
The circumference c of a circle is
c
=
2
π
r
Answer:
you need a picture of the prism
Answer:
The probability density function for the average length of life of the two components is 
Step-by-step explanation:
Exponential distribution:
The exponential probability distribution, with mean m, is described by the following probability density:

In which
is the decay parameter.
Each missile has a length of life governed by the exponential distribution with mean 1 (with measurements in hundreds of hours). Find the probability density function for the average length of life of the two components.
2, each with mean 1 means that 
So the probability density function is:

6 repeating so the answer would be 31.666666..... or round it up 31.666666667
0,8 = 8/10 = 4/5 = 16/20...