Answer:
The probability is 
Step-by-step explanation:
From the question we are told that
The population size is N = 31
The sample size n = 4
Generally the number of way by which the n can be selected from N is mathematically represented as
=>
=> 
=> 
=> 
The number of ways of selecting a particular sample size is is 
Therefore the probability of each simple random sample in this case is mathematically evaluated as

Answer: 38/61+70/61i
Step-by-step explanation:
? What is this math question mean?
That would be.... placoderm fish
Answer:
f(x) = -2x +7
Step-by-step explanation:
The 2-point form of the equation for a line is suitable for this. For points (x1, y1) and (x2, y2), the equation is ...
y = (y2 -y1)/(x2 -x1)(x -x1) +y1
For the given points (0, 7) and (3, 1), the equation is ...
y = (1 -7)/(3 -0)(x -0) +7
y = -6/3x +7 . . . . . . . . simplify.
We can use f(x) for y to get ...
f(x) = -2x +7