At a local college, 204 of the male students are smokers and 306 are non-smokers. Of the female students, 180 are smokers and 420 are non-smokers. A male student and a female student from the college are randomly selected for a survey. What is the probability that both are smokers?

[tex] \frac{1}{ \sqrt{7} -(- 2)} \\ rationalizing \: \: \: the \: \: \: denominator \: \: \: we \: \: \: have \\ = \frac{1}{ \sqrt{7} + 2 } \times \frac{ \sqrt{7} - 2}{ \sqrt{7} - 2} \\ = \frac{ \sqrt{7} - 2}{ {( \sqrt{7} )}^{2} - {(2)}^{2} } \\ = \frac{ \sqrt{7} - 2 }{7 - 4} \\ = \frac{ \sqrt{7} - 2}{3} [/tex]

Hope you could get an idea from here.

Doubt clarification - use comment section.

Given that:

1/(√7 - 2)

The denominator is (√7-2).

We know

The rationalising factor of (√a-b) is (√a+b)

Therefore, the rationalising factor of √7-2 is √7+2.

On rationalising the denominator them

⇛[1/(√7-2)]×[(√7+2)/(√7+2)]

⇛[1(√7+2)]/[(√7-2)(√7+2)]

Since, (a-b)(a+b) = a²-b²

Where, a = √7 and b = √2.

⇛[1(√7+2)]/[(√7)²-(2)²]

⇛[1(√7+2)]/[(√7*7)-(2*2)]

⇛[1(√7+2)]/[7-4]

⇛[1(√7+2)]/3

⇛(√7+2)/3

Hence, the denominator is rationalised.

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Answer: least

Step-by-step explanation: because 0.23 is closer to 1

Least

If you removed the last term from 0.136, it would become 0.13

Compared to 0.25, it is lower.

Answer:

yes less than a min

Step-by-step explanation:

Answer:

11

Step-by-step explanation:

The third ordered pair positive integers that satisfies the equation is (123, 369).

The given parameters;

The third ordered pair of the equation can be determined by using general equation of a circle;

[tex]a^2 + b^2 = r^2\\\\a^2 + b^2 = (123\sqrt{10} )^2\\\\a^2 + b^2 = (\sqrt{151290} )^2\\\\a^2 + b^2 = 151290\\\\a^2 = 151290- b^2\\\\ a= \sqrt{151290 - b^2}[/tex]

The radius of the circle is calculated as;

[tex]r^2 = 151290\\\\r = \sqrt{151290} \\\\r = 388.96[/tex]

The value of a can be obtained by randomly choosing numbers less than the radius as values of b.

[tex]b < r\\\\b < 388.96[/tex]

[tex]a = \sqrt{151290 \ - \ (387)^2} \\\\a = 39\\\\(39, \ 387)\\\\a = \sqrt{151290 \ - \ (333)^2}\\\\a = 201\\\\(201, \ 333)\\\\a = \sqrt{151290 \ - \ (369)^2}\\\\a = 123\\\\(123, \ 369)[/tex]

Thus, the third ordered pair positive integers that satisfies the equation is (123, 369).

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Answer:

A

Step-by-step explanation:

The answer is A because is it asking for a 3 in the hundredths place of the difference. Difference means subtraction. And you can find the hundredth spot in the second place over from the decimal

(ex. 1.23, hundredth place is a 3)

So then you do the math and find the differences.

14.56-9.33=5.23, which has a 3 in the hundredth place.

Answer:

[tex]993,\!600[/tex].

Step-by-step explanation:

There is one way to choose the first character (has to be an [tex]\verb!A![/tex].)

There is one way to choose the last character (has to be a [tex]\verb!1![/tex].)

Since repetition among the letters is not allowed and the letter [tex]\verb!A![/tex] was already reserved for the first character, there would be [tex](26 - 1) = 25[/tex] English alphabet letters available for the second character.

Likewise, with the first and second characters chosen, the third character could be chosen from [tex](26 - 2) = 24[/tex] letters. There would be [tex](26 - 3) = 23[/tex] choices for the fourth letter.

Repetition of the digits is not allowed, either. With the digit [tex]\verb!1![/tex] already reserved for the last character, there would be [tex](10 - 1) = 9[/tex] ways to choose the fifth character (a digit.) There would then be [tex](10 - 2) = 8[/tex] ways to choose the sixth character (also a digit.)

Overall, the number of unique combinations would be:

[tex]\begin{aligned}& 1 \times 1 \times (25 \times 24 \times 23) \times (9 \times 8) \\ =& \; 993,\!600 \end{aligned}[/tex].

======================================================

Explanation:

PDF = probability density function

The given joint PDF is

[tex]f(x,y) = \begin{cases}ax \ \ \ \text{ if } 1 \le x \le y \le 2\\0 \ \ \ \ \ \text{ otherwise}\end{cases}[/tex]

Let's focus on the [tex]1 \le x \le y \le 2[/tex]. Specifically the x term for now. Erasing out the y term, we have the inequality [tex]1 \le x \le 2[/tex] which says x is between 1 and 2, inclusive. We have almost the same story for y, but there's another condition attached to it: y must also be equal to or larger than x.

So let's say x = 1.5. This would mean [tex]1.5 \le y \le 2[/tex]. As another example, x = 1.7  leads to [tex]1.7 \le y \le 2[/tex]. In general, we would say [tex]x \le y \le 2[/tex] where x is between 1 and 2.

As x gets bigger, the range of possible y values gets smaller. If x = 2, then y has no choice but to be 2 as well.

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

Based on that, we'll have a double integral that looks like this:

[tex]\displaystyle V = \int_{1}^{2}\int_{x}^{2}f(x,y)dydx\\\\[/tex]

The outer integral handles the x terms that range from 1 to 2, describing [tex]1 \le x \le 2[/tex]. Note the dx on the outside. The order of the dy and dx matters.

On the inside, we have the integral for dy ranging from x to 2 to describe the interval [tex]x \le y \le 2[/tex]

To have f(x,y) be a PDF, the volume under the f(x,y) surface must be 1, where the volume is based on the bounds set up. So we must have V = 1. We'll use this later.

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

Let's simplify the double integral.

We'll start by computing the inner integral with respect to y.

[tex]\displaystyle V = \int_{1}^{2}\int_{x}^{2}f(x,y)dydx\\\\\displaystyle V = \int_{1}^{2}\int_{x}^{2}\left(ax\right)dydx\\\\\displaystyle V = \int_{1}^{2}\left(axy\Bigg|_{x}^{2}\right)dx\\\\\displaystyle V = \int_{1}^{2}\left(ax(2) - ax(x)\right)dx\\\\\displaystyle V = \int_{1}^{2}\left(2ax - ax^2\right)dx\\\\[/tex]

Then we'll finish it off by integrating with respect to x.

[tex]\displaystyle V = \int_{1}^{2}\left(2ax - ax^2\right)dx\\\\\displaystyle V = \left(ax^2 - \frac{1}{3}ax^3\right)\Bigg|_{1}^{2}\\\\\displaystyle V = \left(a(2)^2 - \frac{1}{3}a(2)^3\right) - \left(a(1)^2 - \frac{1}{3}a(1)^3\right)\\\\\displaystyle V = \left(4a - \frac{8}{3}a\right)-\left(a - \frac{1}{3}a\right)\\\\[/tex]

[tex]\displaystyle V = 4a - \frac{8}{3}a-a + \frac{1}{3}a\\\\\displaystyle V = 3a - \frac{8}{3}a + \frac{1}{3}a\\\\\displaystyle V = \frac{9}{3}a - \frac{8}{3}a + \frac{1}{3}a\\\\\displaystyle V = \frac{9-8+1}{3}a\\\\\displaystyle V = \frac{2}{3}a\\\\[/tex]

Side note: We don't have to worry about the "plus C" integration constant when working with definite integrals.

Recall that V = 1. So,

[tex]\displaystyle V = \frac{2}{3}a\\\\\displaystyle \frac{2}{3}a = 1\\\\\displaystyle a = \frac{3}{2} = 1.5\\\\[/tex]

a = 3/2 is the final answer.

Answer:

If the die is 6 sided then the likely is none (0)

Step-by-step explanation:

Hope this helps!:)

Answer:

I think its 86

Step-by-step explanation:

As the two lines going in the same direction are parallel and angles within parallel lines add to 180.

so 180-94=86

Answer:

20

Step-by-step explanation:

Knowing that it is a 30-gallon bathtub.

And it fills at a rate of 3 gallons per minute.

But also drains 1.5 gallons per minute.

So this is for the first minute.

3 - 1.5 = 1.5

So there will be 1.5 gallons of water in the tub after the first minute.

Now do,

30 ÷ 1.5 = 20

It will take 20 full minutes for the bathtub to fill up.

Answer:

Step-by-step explanation:

You may find this easier if you distribute the minus sign first.

2a^2 -3ab +5b^2 -a^2 +2ab -3b^2

  = (2 -1)a^2 +(-3+2)ab +(5 -3)b^2

  = a^2 -ab +2b^2 . . . . . matches choice D

__

6x -3 -2x +2

  = (6 -2)x +(-3 +2)

  = 4x -1 . . . . . matches choice B

Answer:14

Step-by-step explanation:

Your Answer Is : - 31xz + 16xy - 9yz

A tail length of 23.94 cm is at the 40th percentile for these lizards.

The z score is used to determine by how many standard deviations the raw score is above or below the mean. It is given by:

[tex]z=\frac{x-\mu}{\sigma} \\\\where\ x\ is\ raw\ score, \mu\ is\ mean,\sigma\ is\ standard\ deviation\\\\\\Given\ that:\\\mu=22.5\ cm,\sigma = 3.6\ cm[/tex]

For the 40th percentile, that is z = 40% = 0.4:

[tex]0.4=\frac{x-22.5}{3.6} \\\\x=23.94\ cm[/tex]

A tail length of 23.94 cm is at the 40th percentile for these lizards.

Find out more at: https://brainly.com/question/15016913

Answer:

it's 11

Step-by-step explanation:

Answer:

                                 pop

                                             yes                   no             total

country            yes                  11                      38              49

                        no                       43                     8                51

                         total                54                     46               100

Hope you understand this haha

The answer is in the file. Hope it helps.

Answer:

Step-by-step explanation:Move the decimal point in the divisor and dividend. ...

Place a decimal point in the quotient (the answer) directly above where the decimal point now appears in the dividend.

Divide as usual, being careful to line up the quotient properly so that the decimal point falls into place.

Answer:

112.81 miles

Step-by-step explanation:

304.6 divided by 2.7

Answer:

First ratio:4/3

Second:28/9

Answer:

Follow the explanation below.

Step-by-step explanation:

7x = 48 - 8

7x = 40

x = 40/7

x = 5.714

Answer: 95,800 - 28,766 = 67,034

Step-by-step explanation: hope this helps :)

The answer to the question is

D)  ($9. 60, $9. 84)

Answer:

D

Step-by-step explanation:

Because the discount price is the whole equation 24(1-x),

the original price is 24 technically, and the percent of discount has been given as x...

Answer:

24

the formula of sphere is

[tex]v = \frac{4}{3} {r}^{3} [/tex]

Since we know the volume, and have to find the diameter (twice the radius), we need to determine the radius first.

Hence, using the given data:

[tex]2304\pi = \frac{4}{3} \pi {r}^{3} [/tex]

We can cancel

We can cancel π from each side.

[tex]2304 = \frac{4}{3} {r}^{3} [/tex]

Multiply both sides by

[tex] \frac{3}{4} [/tex]

hope I help you ☺️❤️

Raise [tex]6[/tex] to the second power, [tex]6^{2}[/tex], the subtract r from the result, that should be [tex]6^{2} - r[/tex], since we are not to simplify the expression, that's the answer.

[tex]\huge\text{\bf Hey there!}[/tex]

[tex]\huge\boxed{\mathsf{4x = 96}}\\\\\large\text{DIVIDE 4 to BOTH SIDES}\\\\\huge\boxed{\mathsf{\dfrac{4x}{4} = \dfrac{96}{4}}}\\\\\large\text{CANCEL out: }\rm{\dfrac{4}{4}}\large\text{ because it gives you 1}\\\large\text{KEEP: }\rm{\dfrac{96}{4}}\large\text{ because it helps solve for the x-value}\\\\\large\text{NEW EQUATION: }\huge\boxed{\rm{x = \dfrac{96}{4}}}\\\\\large\text{SIMPLIFY IT\textbf{!}}\\\\\huge\text{x = \bf 24}\\\\\\\huge\text{Therefore, your answer is: \boxed{\textsf{x = 24}}}\huge\checkmark[/tex]

[tex]\huge\textbf{Good luck on your assignment \&}\\\huge\textbf{enjoy your day!}[/tex]

~[tex]\frak{Amphitrite1040:)}[/tex]

56566965577553666645556566667

Answer:

A is correct

Step-by-step explanation:

perimeter is twice the sum of the two adjacent sides

p = 2(x + (2x³ - 3x + 4))

p = 2(2x³ - 2x + 4)

p = 4x³ - 4x + 8

Answer:

142

Step-by-step explanation:

Median is the MID Number