The best answer is C.
u+2b=22
Unicycles have one wheel and bicycles have two, so the coefficient of 2 should go before the variable representing each bike.
It should equal 22 because 15 represents the total number of seats and not wheels.
Answer:
144cm²
Step-by-step explanation:
Area of square A Aa = La²
Area of square B Ab= Lb²
If the length of each side of square B is 4cm greater than the length of each side of square A, then;
Lb = La + 4 ... 1
Also if the area of square B is 70cm² greater than the area of square A, then;
Ab = Aa + 70
Since Aa = La² and Ab = Lb²
Lb² = La² + 70 ...2
Substitute 1 into 2;
(La+4)² = La²+70
Expand
La²+8La+16 = La²+80
8La+16 = 80
8La = 80 - 16
8La = 64
La = 64/8
La = 8cm
Since Lb = La + 4
Lb = 8 + 4
Lb = 12cm
Area of square B = Lb²
Area of square B = 12²
Area of square B = 144cm²
Step-by-step explanation:
idioms isnssid mbv dis cic ejbdie
Answer:
The expected value of X is
and the variance of X is 
The expected value of Y is
and the variance of Y is 
Step-by-step explanation:
(a) Let X be a discrete random variable with set of possible values D and probability mass function p(x). The expected value, denoted by E(X) or
, is

The probability mass function
of X is given by

Since the bus driver is equally likely to drive any of the 4 buses, the probability mass function
of Y is given by

The expected value of X is
![E(X)=\sum_{x\in [28,32,42,44]} x\cdot p_{X}(x)](https://tex.z-dn.net/?f=E%28X%29%3D%5Csum_%7Bx%5Cin%20%5B28%2C32%2C42%2C44%5D%7D%20x%5Ccdot%20p_%7BX%7D%28x%29)

The expected value of Y is
![E(Y)=\sum_{x\in [28,32,42,44]} x\cdot p_{Y}(x)](https://tex.z-dn.net/?f=E%28Y%29%3D%5Csum_%7Bx%5Cin%20%5B28%2C32%2C42%2C44%5D%7D%20x%5Ccdot%20p_%7BY%7D%28x%29)

(b) Let X have probability mass function p(x) and expected value E(X). Then the variance of X, denoted by V(X), is
![V(X)=\sum_{x\in D} (x-\mu)^2\cdot p(x)=E(X^2)-[E(X)]^2](https://tex.z-dn.net/?f=V%28X%29%3D%5Csum_%7Bx%5Cin%20D%7D%20%28x-%5Cmu%29%5E2%5Ccdot%20p%28x%29%3DE%28X%5E2%29-%5BE%28X%29%5D%5E2)
The variance of X is
![E(X^2)=\sum_{x\in [28,32,42,44]} x^2\cdot p_{X}(x)](https://tex.z-dn.net/?f=E%28X%5E2%29%3D%5Csum_%7Bx%5Cin%20%5B28%2C32%2C42%2C44%5D%7D%20x%5E2%5Ccdot%20p_%7BX%7D%28x%29)


The variance of Y is
![E(Y^2)=\sum_{x\in [28,32,42,44]} x^2\cdot p_{Y}(x)](https://tex.z-dn.net/?f=E%28Y%5E2%29%3D%5Csum_%7Bx%5Cin%20%5B28%2C32%2C42%2C44%5D%7D%20x%5E2%5Ccdot%20p_%7BY%7D%28x%29)


Answer:
B
Step-by-step explanation:
3x-7 <-4
Firstly solve this.
+7 +7
3x<3
÷3 ÷3
x<1
And because the inequality symbol isn't "equal to", the circle isn't coloured in.
The line will go from 1 to behind 0