If y=12, what is the value of 85y+8-80y?

A bookcase contains 2 statistics books and 5 biology books. if 2 books are chosen at random, the chance that both are statistics

xenn [34]

Answer:

The chance that both are statistics books is $\frac{1}{21}$

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.

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

Combination of n elements taken from k to k is called each of the ways of choosing k different elements from the n of the original set. That is, it is called combinations of m elements taken from k to k to all the possible groupings that can be made with the m elements. It is expressed as:

$Cn,k=\frac{n!}{k!*(n-k)!}$

Remember that the factorial of a positive integer n is defined as the product of all the natural numbers before or equal to it.

A bookcase contains 2 statistics books and 5 biology books. The total number of book is 7.

2 books are chosen at random. The total outcomes can be obtained by selection of two books from seven books which is represented as follows:

$C7,2=\frac{7!}{2!*(7-2)!}=\frac{7!}{2!*5!}=\frac{5040}{2*120} =\frac{5040}{240} =21$

The selection of two statistics book from two statistics book is represented as follows:

$C2,2=\frac{2!}{2!*(2-2)!}=\frac{2!}{2!*0!}=\frac{2}{2*1} =\frac{2}{2} =1$

Then, the probability is:

$P(A)=\frac{C2,2}{C7,2}$

$P(A)=\frac{1}{21}$

The chance that both are statistics books is $\frac{1}{21}$

7 0

2 years ago

the width of a rectangle is x centimetres and its length is (x+ 2) cm. Write down an expression for the perimeter of the rectang

abruzzese [7]

Perimeter = length + length + width + width

P= (x + 2) + (x + 2) + x + x
P = x + 2 + x + 2 x + x
P= 4x + 4

Some teachers then want you to pull out the common factor of 4. If yours does, it’s P = 4(x + 1)

3 0

2 years ago

Read 2 more answers

Arie ran an equal number of miles each day for 12 days. He ran 60 miles total.

VLD [36.1K]

Answer:

5 miles

Step-by-step explanation:

60 miles / 12 days

5 miles

5 0

3 years ago

Read 2 more answers

Point JJJ is located at (-4, 4)(−4,4)left parenthesis, minus, 4, comma, 4, right parenthesis. Select all of the following that a

In-s [12.5K]

Answer:

(-4, 8), (-4, 0), (0, 4) and (-4, 0)

Step-by-step explanation:

Given that point J is located at (-4, 4). The point4 units from point J can either be up, down, left or right. Hence:

The point 4 units up of point J = (-4, 4 + 4) = (-4, 8)

The point 4 units down of point J = (-4, 4 - 4) = (-4, 0)

The point 4 units right of point J = (-4 + 4, 4) = (0, 4)

The point 4 units left of point J = (-4, 4 - 4) = (-4, 0)

Therefore the points that are 4 units from point J are (-4, 8), (-4, 0), (0, 4) and (-4, 0).

8 0

2 years ago

A number cube has the numbers

kogti [31]

Answer:

that is based on luck u could get 5 everytime or none, depends on what roll

7 0

3 years ago