The number e is the base of the?

. At a clothing store, 12 people purchased blue sweaters, 8 purchased green sweaters, 4 purchased gray sweaters, and 7 purchased

DedPeter [7]

Answer:

The probability that they purchased a green or a gray sweater is $\frac{12}{31}$

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.

$P(A)=\frac{number of favorable cases}{number of possible cases}$

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:

$P(A)=\frac{8}{31}$

$P(B)=\frac{4}{31}$

P(A⋂B) = 0

Then:

P(A∪B)= P(A) + P(B)

P(A∪B)= $\frac{8}{31}+ \frac{4}{31}$

P(A∪B)= $\frac{12}{31}$

The probability that they purchased a green or a gray sweater is $\frac{12}{31}$

5 0

3 years ago

You are organizing books on the shelf. Each book has a width of 3/4 inches. write and solve an equality for the numbers of books

Lunna [17]

3/4 = 0.75 inches

24 inches / 0.75 inches

= 32 books

6 0

2 years ago

In a triangle, the sum of the measures of the first two angles is 12 less than the measure of the third angle. In addition, the

PSYCHO15rus [73]

the sum of the internal angles of a triangle are equal to 180 degrees.

once i remembered that the problem became a lot easier.

let a, b, and c be the angles of the triangle.

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let a = 2*b

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let c = a+b-12

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the above two statements are given.

since the sum of the internal angles of a triangle are equal to 180, then we have a third equation to work with which is

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a + b + c = 180

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we now have 3 equations for 3 unknowns and we should be able to solve for each of the unknowns.

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it looks like the easiest thing is to solve for b. once we find b, the rest should fall into place very nicely.

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since a = 2*b, we can substitute 2*b for a in the equation a + b + c = 180.

that equation then becomes 2*b + b + c = 180 which becomes 3*b + c = 180.

looking at the equation c = a + b - 12, we solve for b as follows:

since we know that a = 2 * b, we can substitute 2*b for a and the equation becomes c = 2*b + b - 12 which becomes c = 3*b - 12.

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the equation we are working with is 3*b + c = 180 which originally started as a + b + c = 180.

we can substitute 3*b - 12 for c and the equation becomes

3*b + 3*b - 12 = 180 which becomes 6*b = 192 after adding 12 to both sides and combining like terms.

dividing both sides of the equation by 6 and we get b = 32 degrees.

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we have b = 32 degrees.

we have a = 2 * b so a = 64 degrees.

we have c = a + b - 12 which becomes c = 32 + 64 - 12 which becomes c = 96 - 12 which becomes c = 84 degrees.

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substituting in the equation a + b + c = 180, we get 32 + 64 + 84 = 180 which becomes 96 + 84 = 180 which becomes 180 = 180.

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answer is:

a

4 0

3 years ago

James went on holiday to America. The summary table below shows all his expenses during this trip. Cost in $ Cost in £ Flights £

VLD [36.1K]

Answer:

sorry I need points lng ehhh

Step-by-step explanation:

sorry

3 0

2 years ago

Please help me with this.

Dmitrij [34]

Answer:

the answer is 12

Step-by-step explanation:

4 0

3 years ago