Answer:
7
Step-by-step explanation:
Answer:
Now we can calculate the second moment with the following formula:
And replacing we got:
And the variance is given by:
And replacing we got:
And the standard deviation is just the square root of the variance:
Step-by-step explanation:
Previous concepts
For this case we define the random variable X =" how many children the couple will have" and we know the following distribution:
X 1 2 3
P(X) 0.52 0.250 0.230
The expected value of a random variable X is the n-th moment about zero of a probability density function f(x) if X is continuous, or the weighted average for a discrete probability distribution, if X is discrete.
The variance of a random variable X represent the spread of the possible values of the variable. The variance of X is written as Var(X).
Solution to the problem
For this case we can find the expected value with the following formula:
And replacing we got:
Now we can calculate the second moment with the following formula:
And replacing we got:
And the variance is given by:
And replacing we got:
And the standard deviation is just the square root of the variance:
Answer:
3x^3-2x^2-19x-6
Step-by-step explanation:
= 3x^2x+3x^2(-3)+7xx+7x(-3)+2x+2(-3)
= 3x^3 - 2x^2 - 19x - 6
Key - (^) means exponent
We know that
<span>pentagon A is the smaller pentagon----> length side 4 cm
and
</span><span>pentagon B is the larger pentagon-----> length side 6 cm
so
</span><span>the scale factor from pentagon B to pentagon A=length side B/length side A
6/4----> 3/2---> 1.5
the answer is the option
</span><span>B) 1.5 </span>
Answer:
5
Step-by-step explanation:
BD = 16, so:
2y − 2 + y + 3 = 16
3y + 1 = 16
3y = 15
y = 5