<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:
The number of packages Justin needs to buy to get x cards is x divided by 3.
- <u>Rule as an algebraic expresssion:</u>

Explanation:
This is a direct variation problem.
Since each package has the same number of cards, the number of cards is proportional to the number of packages.
12 baseball cards in 4 packages means that there are 12/4 = 3 cards per package, so:
- The number of cards is 3 times the number of packages.
- The number of packages is the number of cards divided by the number of 3.
So, the <em>rule in words</em> for the number of packages Justin needs to buy x cards is one third of x. This table may help you to visualize it:
Number of packages: 1 2 3 4 5
Number of cards: 3 6 9 12 15
To find the <em>algebraic expression</em> that describes the same rule, you can set the following proportion:

Where y is the number of packages and x is the number of cards.
And from that you solve for y:

The answer would be 105.41
Explantaion: 122 • 0.2=24.4
122-24.4=97.6
97.6•0.08=7.808 which rounded to the nearest hundredths would be 7.81 then 97.6+7.81=105.41
Answer: If you wanting to find the slope, the answer would be m = -10/3
Step-by-step explanation: Use the slope formula to find the slope m.
Hope this helps you out! ☺
The answer to day 3 is A :)