<span>When you are sampling from a small finite lot, the hypergeometric distribution applies. The binomial is a poor approximation in this case.
The general equation for the hypergeometric where aCx means the number of combinations of a items selected x at-a-time.:
P(x) =[(aCx)(N-aCn-x)]/NCn
Where
N is the lot size = 20
a is the number of defectives in the lot = 3.
x is the number of defectives in the sample.
n is the sample size = 2.
A. The probability that the first item is defective is
P(x=1) = [(3C1)(17C1)]/(20C2)
= (3)(17)/190 = 0.268
The probability that the second item is defective is
P(x = 1) = [(2C1)(17C1)]/(19C2) = (2)(17)/171 = 0.199.
So the total probability is (0.268)(0.199) = 0.0532
B. The probability that the first item is good is:
P(x = 0) = (3C0)(16C2)]/20C2 = (1)(120)/190 = 0.632
The probability that the second item is defective is
P(x = 0) =[(3C0)(16C2)]/19C2
= (1)(120)/171 = 0.670.
The total probability is 0.632(0.670) = 0.4234</span>
Answer:
g inverse = (1,a),(2,b),(c,3),(4,d)
Step-by-step explanation:
I think the third part of the question should be (c,3) not (2,3)
if it's (2,3) then the inverse becomes (3,2)
Answer:
A
Step-by-step explanation:
In (4,5) the difference between 5 and 4 is 1, the same applies for (8,9), therefore y=x+1 is a linear function of y=x+1
So using this function: (1,2),(2,3),(3,4)(4,5) etc
Answer: (1,-1)
Step-by-step explanation:
- You can multiply the first equation by -1
- Add the equations.
- Solve for x, as following:
- Substitute the value of x into any of the original equations and then you must solve for y:
Therefore, the solution is: (1,-1)
