The answers are:
P(9, 2) = 72
P(5, 5) = 120
P(7, 7) = 5040
These are examples of permutations. The problems are asking us to find the total number of ways an event can happen.
In the first case, P(9, 2), we are asked to find the ways that 2 things can be chosen out of a group of 9.
9 x 8 = 72
P(5, 5) = 5 x 4 x 3 x 2 x 1
P(7, 7) = 7 x 6 x 5 x 4 x 3 x 2 x 1
Using the binomial distribution, the probabilities are given as follows:
- 0.3675 = 36.75% probability that more than 4 weigh more than 20 pounds.
- 0.1673 = 16.73% probability that fewer than 3 weigh more than 20 pounds.
- Since P(X > 7) < 0.05, it would be unusual if more than 7 of them weigh more than 20 pounds.
<h3>What is the binomial distribution formula?</h3>
The formula is:


The parameters are:
- x is the number of successes.
- n is the number of trials.
- p is the probability of a success on a single trial.
The values of the parameters for this problem are:
n = 10, p = 0.4.
The probability that more than 4 weigh more than 20 pounds is:

In which:

Then:






Hence:


0.3675 = 36.75% probability that more than 4 weigh more than 20 pounds.
The probability that fewer than 3 weigh more than 20 pounds is:
P(X < 3) = P(X = 0) + P(X = 1) + P(X = 2) = 0.0061 + 0.0403 + 0.1209 = 0.1673
0.1673 = 16.73% probability that fewer than 3 weigh more than 20 pounds.
For more than 7, the probability is:





Since P(X > 7) < 0.05, it would be unusual if more than 7 of them weigh more than 20 pounds.
More can be learned about the binomial distribution at brainly.com/question/24863377
#SPJ1
X + 2/3 = 2x - 4/2
2/3 + 4/2 = 2x - x
2 + 2/3 = x
8/3 = x
I hope this helps!
<span>19 − 6( − k − 2)
Distribute -6:
= 19 + 6k + 12
Combine like terms:
= 6k + 31
Answer: </span>6k + 31