Find the area of the circle.<br> Use 3.14 for .

PLEASE ANSWER CORRECTLY! WILL GIVE BRAINLIEST!

vaieri [72.5K]

Answer:

0.7938

Step-by-step explanation:

z1 = (125-100)/15 = 1.667

P( < 125) = 0.9522

z2 = (85-100)/15 = -1

P( > 85) = 0.8413

0.9522 + 0.8413 - 1 = 0.7935

4 0

3 years ago

A denotes an mn matrix. Determine whether the statement is true or false. Justify your answer. The row space of AT is the same a

ziro4ka [17]

Answer: true

Step-by-step explanation:

For an m*n matrix, the column space of A will be a space formed by the lineal combination of all the columns of A.

column space = a1*c1 + a2*c2 + ...

where a1, a2, ... are scalars, and c1 is the vector of column 1.

Then we should write:

Column space = a1*(A₁₁, A₂₁, A₃₁, ...) + a2*(A₁₂, A₂₂, A₃₂, ...) + ...

Now, the transpose is defined as:

[At]₁₃ = A₃₁

Here i used the element with subindex 3 and 1, but is the same for every subindex.

Notice that if A is m*n, then [At] is n*m

Now, the row space of [At] will be, same as before.

Row space = b1*r1 + b2*r2 + ...

Where b1, b2, ... are scalars and the r's are the vector of each row.

= b1*( [At]₁₁ , [At]₁₂, [At]₁₃, ...) + b2*([At]₂₁, [At]₂₂, [At]₂₃, ...) + ...

Now we replace each term of the transpose by the associated element in the original matrix.

= b1*( A₁₁, A₂₁, A₃₁, ...) + b2*(A₂₁, A₂₂, ...) + ....

If we take:

b1 = a1, b2 = a2, b3 = a3, ...

We will have that the row space of [At] is the same as the column space of A.

4 0

2 years ago

38<br> Is that a perfect square

fomenos

No cuz u have to be able to divide by 4 i think

7 0

3 years ago

Read 2 more answers

Max is reading a book. He has already read 1/4 of the book. If he stopped at the top of page 67, how many pages are there in the

dedylja [7]

Let p represent # of pages in the book.

Then (1/4)p = 67. Solve for p by mult. both sides of this equation by 4:

p = 268 (pages)

4 0

3 years ago

Read 2 more answers

In the 2000 presidential election, three candidates split the vote as follows:

Lera25 [3.4K]

Answer:

c 23 and 0.46 are statistics and 0.484 is a parameter

True. For this case the value 0.46 represent t statistic since from the sample obtained we can calculate the sample proportion of people who voted for Gore like this:

$\hat p_{Gore]=\frac{X}{n}=\frac{23}{50}=0.46$

Where X represent the people with the characteristic desired in the random sample selected.

So then we can say that 23 and 0.46 represent statistics since comes from the sample. And the value 0.484 is obtained from the population so then represent a parameter.

Step-by-step explanation:

Previous concepts

A parameter is any "numerical quantity that characterizes a given population or some aspect of it". For this case we are interested on proportions and we denote the population proportion by $p$

A statistic is "used to estimate the value of a population parameter". In other words is just an estimation of the population parameter of interest. Four our case the sample proportion denoted by $\hat p$ represent the statistic for this case.

Solution for the problem

a 0.46 and 0.484 are statistics

False. 0.484 is not an statistic since it's the outcome from the original population and would represent the parameter "proportion of people who vote for Gore"

b 50 and 23 are statistics and 0.484 is a parameter

False. The sample size is not an statistic is just a value selected in order to calculate the statistic.

c 23 and 0.46 are statistics and 0.484 is a parameter

True. For this case the value 0.46 represent t statistic since from the sample obtained we can calculate the sample proportion of people who voted for Gore like this:

$\hat p_{Gore]=\frac{X}{n}=\frac{23}{50}=0.46$

Where X represent the people with the characteristic desired in the random sample selected.

So then we can say that 23 and 0.46 represent statistics since comes from the sample. And the value 0.484 is obtained from the population so then represent a parameter.

6 0

3 years ago

Find the area of the circle. Use 3.14 for .