423 = 100 + 100 + 100 + 100 + 10 + 10 + 3
hope this helps
Answer:
The value increases
Step-by-step explanation:
the smaller the divisor, the larger the quotient.
Answer:
13 meters
Step-by-step explanation:
Adjacent sides form half the perimeter, so the sum of the unknown side and the given side is 34/2 = 17 meters.
4 meters + width = 17 meters
width = 13 meters . . . . . subtract 4 meters
Answer:
a) 
And replacing we got:
b) ![E(80Y^2) =80[ 0^2*0.45 +1^2*0.2 +2^2*0.3 +3^2*0.05]= 148](https://tex.z-dn.net/?f=%20E%2880Y%5E2%29%20%3D80%5B%200%5E2%2A0.45%20%2B1%5E2%2A0.2%20%2B2%5E2%2A0.3%20%2B3%5E2%2A0.05%5D%3D%20148)
Step-by-step explanation:
Previous concepts
In statistics and probability analysis, the expected value "is calculated by multiplying each of the possible outcomes by the likelihood each outcome will occur and then summing all of those values".
The variance of a random variable Var(X) is the expected value of the squared deviation from the mean of X, E(X).
And the standard deviation of a random variable X is just the square root of the variance.
Solution to the problem
Part a
We have the following distribution function:
Y 0 1 2 3
P(Y) 0.45 0.2 0.3 0.05
And we can calculate the expected value with the following formula:
And replacing we got:
Part b
For this case the new expected value would be given by:
And replacing we got
Answer:
k=2
Problem:
if the equation x^2 +(k+2)x+2k=0 has equal roots,then the value of k is ..
Step-by-step explanation:
Since the coefficient of x^2 is 1, we can use this identity to aid us: x^2+bx+(b/2)^2=(x+b/2)^2.
So we want the following:
[(k+2)/2]^2=2k
Apply the power on the left:
(k+2)^2/4=2k
Multiply both sides by 4:
(k+2)^2=8k
Expand left side:
k^2+4k+4=8k *I used identity (x+c)^2=x^2+2xc+c^2
Subtract 8k on both sides:
k^2-4k+4=0
Factor using the identity mentioned a couple lines above:
(k-2)^2=0
Since zero squared is zero, we want k-2=0.
Adding both sides by 2 gives k=2.
