Ask question

Ask question

All categories

2 years ago

11

Which of the following is the difference of two squares?

1 answer:

Blizzard [7]2 years ago

5 0

Answer: C

Step-by-step explanation:

$25a^{2}=(5a)^{2}$ and $36b^{6}=(6b^{3})^{2}$

You might be interested in

Plz help me thank you. 4 cm of the ice tray

disa [49]

I had to do this and it’s fake, my whole class got it wrong even though we all put the right answer so ya

6 0

3 years ago

Read 2 more answers

Calculate the sample mean and sample variance for the following frequency distribution of heart rates for a sample of American a

spin [16.1K]

Answer:

$Mean = 68.9$

$s^2 =18.1$ --- Variance

Step-by-step explanation:

Given

$\begin{array}{cccccc}{Class} & {51-58} & {59-66} & {67-74} & {75-82} & {83-90} \ \\ {Frequency} & {6} & {3} & {11} & {13} & {4} \ \end{array}$

Solving (a): Calculate the mean.

The given data is a grouped data. So, first we calculate the class midpoint (x)

For 51 - 58.

$x = \frac{1}{2}(51+58) = \frac{1}{2}(109) = 54.5$

For 59 - 66

$x = \frac{1}{2}(59+66) = \frac{1}{2}(125) = 62.5$

For 67 - 74

$x = \frac{1}{2}(67+74) = \frac{1}{2}(141) = 70.5$

For 75 - 82

$x = \frac{1}{2}(75+82) = \frac{1}{2}(157) = 78.5$

For 83 - 90

$x = \frac{1}{2}(83+90) = \frac{1}{2}(173) = 86.5$

So, the table becomes:

$\begin{array}{cccccc}{x} & {54.5} & {62.5} & {70.5} & {78.5} & {86.5} \ \\ {Frequency} & {6} & {3} & {11} & {13} & {4} \ \end{array}$

The mean is then calculated as:

$Mean = \frac{\sum fx}{\sum f}$

$Mean = \frac{54.5*4+62.5*3+70.5*11+78.5*13+86.5*4}{6+3+11+13+4}$

$Mean = \frac{2547.5}{37}$

$Mean = 68.9$ -- approximated

Solving (b): The sample variance:

This is calculated as:

$s^2 =\frac{\sum (x - \overline x)^2}{\sum f - 1}$

So, we have:

$s^2 =\frac{(54.5-68.9)^2+(62.5-68.9)^2+(70.5-68.9)^2+(78.5-68.9)^2+(86.5-68.9)^2}{37 - 1}$

$s^2 =\frac{652.8}{36}$

$s^2 =18.1$ -- approximated

5 0

2 years ago

Complete the synthetic division problem below.

rewona [7]

Answer:

B

Step-by-step explanation:

- 2 | 2 2 - 2 4

↓ - 4 4 - 4

--------------------------

2 - 2 2 0 ← remainder

Since the remainder = 0 then (x + 2) is a factor

quotient = 2x² - 2x + 2

4 0

2 years ago

In a newspaper poll concerning violence on television, 589 people were asked, "What is your opinion of the amount of violence on

abruzzese [7]

Answer:

(a) $P(Y'|M)\approx 0.3297$

(b) $P(Y|M')\approx 0.8323$

(c) $P(Y'|M')\approx 0.1323$

Step-by-step explanation:

Given table is

Yes No Don't Know Total

Men 162 92 25 279

Women 258 41 11 310

Total 420 133 36 589

According the the conditional probability, if A and B are two event then

$P(A|B)=P(\frac{A}{B})=\frac{P(A\cap B)}{P(B)}$

We need to find the following probabilities.

Let Y is the event "saying yes," and M is the event "being a man."

(a)

$P(Y'|M)=\frac{P(Y'\cap M)}{P(M)}$

$P(Y'|M)=\frac{\frac{92}{589}}{\frac{279}{589}}$

$P(Y'|M)=\frac{92}{279}$

$P(Y'|M)=0.329749103943$

$P(Y'|M)\approx 0.3297$

(b)

$P(Y|M')=\frac{P(Y\cap M')}{P(M')}$

$P(Y|M')=\frac{\frac{258}{589}}{\frac{310}{589}}$

$P(Y|M')=\frac{258}{310}$

$P(Y|M')=0.832258064516$

$P(Y|M')\approx 0.8323$

(c)

$P(Y'|M')=\frac{P(Y'\cap M')}{P(M')}$

$P(Y'|M')=\frac{\frac{41}{589}}{\frac{310}{589}}$

$P(Y'|M')=\frac{41}{310}$

$P(Y'|M')=0.132258064516$

$P(Y'|M')\approx 0.1323$

5 0

3 years ago

What is the measure of angle ACB in this triangle

Mrrafil [7]

So, angles A and B added together is 130° which makes the whole angle = 180°-130°=50°

The answer is 180° because it is a supplementary angle and all supplementary angles equal 180° so, all the angles added makes 180°

7 0

3 years ago