Answer:
The probability that they purchased a green or a gray sweater is 
Step-by-step explanation:
Probability is the greater or lesser possibility of a certain event occurring. In other words, probability establishes a relationship between the number of favorable events and the total number of possible events. Then, the probability of any event A is defined as the quotient between the number of favorable cases (number of cases in which event A may or may not occur) and the total number of possible cases. This is called Laplace's Law.

The addition rule is used when you want to know the probability that 2 or more events will occur. The addition rule or addition rule states that if we have an event A and an event B, the probability of event A or event B occurring is calculated as follows:
P(A∪B)= P(A) + P(B) - P(A∩B)
Where:
P (A): probability of event A occurring.
P (B): probability that event B occurs.
P (A⋃B): probability that event A or event B occurs.
P (A⋂B): probability of event A and event B occurring at the same time.
Mutually exclusive events are things that cannot happen at the same time. Then P (A⋂B) = 0. So, P(A∪B)= P(A) + P(B)
In this case, being:
- P(A)= the probability that they purchased a green sweater
- P(B)= the probability that they purchased a gray sweater
- Mutually exclusive events
You know:
- 8 purchased green sweaters
- 4 purchased gray sweaters
- number of possible cases= 12 + 8 + 4+ 7= 21
So:
Then:
P(A∪B)= P(A) + P(B)
P(A∪B)= 
P(A∪B)= 
<u><em>The probability that they purchased a green or a gray sweater is </em></u>
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Associative property works in addition and multiplication.
Associative property in Addition: (a + b)+ c = a + (b + c)
Associative property in Multiplication: (a x b) x c = a x (b x c)
Associative property in Subtraction: (a - b) - c is not equal to a - (b - c)
Associative property in Division: (a divided by b) divided by c is not equal to a divided by (b divided by c).
Thus, associative property is not true for all integers.
Answer:
Step-by-step explanation:
Mean roughly means the average of all the results. Add all of them up and divide it by the number of items there are. Median, basically means, you line them up from low to high numerically and the middle number.
There are

such strings, provided that the ordering of the bits doesn't matter.