In a class of 29 students, 20 have a brother and 8 have a sister. There are 3 students who do not have any siblings. What is the probability that a student chosen randomly from the class is an only child?

Answer:

4x^2 - 12x +9

Step-by-step explanation:

The figure is a square.

the area of a square is = side^2

area = (2x-3)^2 = 4x^2-12x +9

thanks to rule of the square of a binomial, we can skip this passage:

(2x-3)(2x-3) = 4x^2-6x-6x+9 =4x^2-12x +9

Answer:

4x²−12+9

Steps:

2x(2x−3)−3(2x−3)

4x²−6−3(2x−3)

4x²−6x−6x+9

4x²−12x+9

Answer: 2.49 s

Step-by-step explanation:

Given

Rock is dropped from a height of [tex]h=100\ ft[/tex]

Using the equation of motion [tex]h=ut+\frac{1}{2}at^2[/tex]

here, [tex]u=0[/tex] (Rock is dropped)

[tex]a=g[/tex]

Putting values

[tex]\Rightarrow 100=0+\dfrac{1}{2}gt^2\\\\\Rightarrow t^2=\dfrac{2h}{g}=\dfrac{2\times 100}{32.2}\\\\\Rightarrow t=\sqrt{6.211}=2.49\ s[/tex]

Answer:

Independent samples t test

Step-by-step explanation:

The experiment performed above, required the independent samples t test as it invilves two seperate and distinct, otherwise called independent groups whereby one group has no effect on the outcome of the other. The means a ND standard deviation of the first group (4 year Olds who attend part time daycare) and the other group (4 year Olds who do not attend part time daycare). Hence, the comparison can be made using the two independent samples t test ;

With possible hypothesis relation being :

H0 : μ1 = μ2

H1 : μ1 ≠ μ2

Answer:

48 cm

Step-by-step explanation:

If it's square and the area is 144, then the sides are each 12cm (a = l x w, 144 = 12 x 12)

12cm x 4 sides = 48cm

Answer:

48

Step-by-step explanation:

The area is 144 cm².

A = s²

144 = s²

[tex]\sqrt{144\\}[/tex] = s

12 = s

photo frame is a square.

perimeter of a square = 4 * s

P = 4 *s

P = 4 (12)

P = 48

Answer:

z = -2

Step-by-step explanation:

7z + 4 - 9z = 8 (The first step is to combine like terms, so 7z -9z = -2z)

-2z + 4 = 8 (Subtract 4 on each side)

-2z = 4 (Divide each side by -2)

z = -2

You can plug -2 back in to check, and you get:

7(-2) + 4 -9(-2) = 8

-14 + 4 + 18 = 8

8 = 8

Hopefully, this helped. Good luck!

Answer:

z=-2

Step-by-step explanation:

7z+4-9z=8

7z-9z=8-4

-2z=4 divide by-2

z=-2

Answer:

the volume of the cylinder is 785 units^2

Step-by-step explanation:

The computation of the volume of the cylinder is shown below:

Given that

The diameter is 10 units

So, the radius is half of the diameter i.e. 5 units

The height would be twice of the radius i.e. 10 units

Now the volume of the cylinder is

=πr^2h

r denotes the radius

And h denotes the height

= 3.14 × 5^2 × 10

= 785 units^2

Hence, the volume of the cylinder is 785 units^2

Answer:

-5, -3, 9, 11, 15, 22

Step-by-step explanation:

idrk how to explain

Answer:

1:40

Step-by-step explanation:

because there are two red continuous so double the no. of total marbles.

Answer:

All real Numbers, which basically ,means infinite solutions

Step-by-step explanation:

Answer:

440,000!!! LOL

Step-by-step explanation:

Answer:

440,000

Step-by-step explanation:

I got 440,000 as an answer because I did

400,000

+40,000

________

440,000

You could work from the ones to the hundred thousandths.

First add the zeros, then work to the thousandths. 0+0=0, 0+0=0,0+0=0,0+0=0,0+4=4, 4+0=4.

Therefore, 400,000+40,000=440,000.

Step-by-step explanation:

Answer attached...

Hope it helps :)

Answer:

Step-by-step explanation:

Given

To find

Solution

So

Answer:

1.01 or 1.0

Step-by-step explanation:

Answer:

a = -7/17

Step-by-step explanation:

Add -4a to -2a

This makes -6a. Then you add 6a to the left to cancel it out, but you must also add 6a to the right of the =

Then you have -7 = 17a

Divide 17 from both sides and you have -7/17 = a

Step-by-step explanation:

Hey there!

[tex]\tt{\dfrac{\dfrac{1}{x^2} + \dfrac{2}{y}}{\dfrac{5}{x} - \dfrac{6}{y^2}}}[/tex]

So, what we can do here is first take the Least Common Multiple here, on both Numerator and Denominator.

[tex]\tt{\dfrac{\dfrac{y + 2y^2 (1)}{x^2 y (2)}}{\dfrac{5y^2 - 6x (3) }{xy^2 (4)}}}[/tex]

[The number in brackets is for the next step :-

When we will further simplify it, we will multiply 1st with 4th and 2nd with 3rd.

[tex]\tt{\dfrac{y + 2y^2 \times xy^2 }{x^2 y \times 5y^2 - 6x }}[/tex]

[tex]\tt{\dfrac{y + 2y^2 \times y }{x \times 5y^2 - 6x }}[/tex] is the framed answer.

Answer:

[tex]\frac{y(y+2x^2)}{x(5y^2-6x}[/tex]

Step-by-step explanation:

Lets do the numerator and denominator seperately:

Numerator:

1/x^2 + 2/y

Find common denominator and add these 2 fractions:

This is x^2y (I just multiplied the 2 denominators together’

Now, do what you have done to x^2 to make it x^2y, ie. multiplied by y, to the 1. This = y

And do what you have done to y to make it x^2y, ie. multiplied by x^2, to the 2. This = [tex]2^{2}[/tex]

Now, arrange all numbers we have found into the correct order in the fraction. This is:

[tex]\frac{y+2x^{2}}{x^{2} y}[/tex]

Denominator:

5/x - 6/y^2

Find the common denominator  and subtract these two fractions:

This is xy^2

Now, do what you have done to x to make it xy^2, ie. multiply by y^2, to the 5. This = 5y^2

And do what you have done to the y^2 to make it xy^2, ie. multiply by x, to the 6, this is = 6x

Now, arrange all the numbers we have found into the correct order in the fraction

[tex]\frac{5y^{2}-6x}{xy^2}[/tex]

Now that we have the numerator and the denominator, we can solve the equation.

The original question asks us to divide the 2 fractions, so:

[tex]\frac{y+2x^{2}}{x^{2} y}[/tex]  divided by [tex]\frac{5y^{2}-6x}{xy^2}[/tex]

For the division of fractions, you just have to multiply the inverse of the 2nd fraction by the first, so

[tex]\frac{y+2x^{2}}{x^{2} y}[/tex] x [tex]\frac{xy^2}{5y^2-6x}[/tex]

Use cross multiplication to simplify the above expression to:

[tex]\frac{y(y+2x^2)}{x(5y^2-6x}[/tex]

Hope this helps, sorry its long ...

Answer: hi thanks for the five

Step-by-step explanation:

Answer: EAD

Explanation: The angle mark is in between the points E, A, and D.

Answer:

acute

Step-by-step explanation:

Step-by-step explanation:

y-15=x^2+10x

y-15+25=x^2+10x+25

y+10=(x+5)^2

Answer:

a) 0.071

b) 0.884

Step-by-step explanation:

a)

7.1 * 10^(2) = 7.1 * 0.01 = 0.071

b)

(6.8 * 10^2) * (1.3 * 10^(-3)) = 6.8 * 1.3 * 10^2 * 10^(-3) = 8.84 * 10^(-1) = 8.84 * 0.1 = 0.884

Answer:

a) 0.071

b) 0.884

Step-by-step explanation:

b) explanation

Group coefficients together and exponents together to multiply numbers in scientific notation.

(6.8 ⋅ 1.3) (10^2 ⋅ 10^−3)

Multiply 6.8 by 1.3

8.84 (10^2 ⋅ 10^−3)

Use the power rule a^m a^n = a^m+n  to combine exponents.

8.84 ⋅ 10^2 − 3

Subtract 3 from 2

8.84 ⋅ 10^ − 1

Convert  8.84 ⋅ 10^ − 1

from scientific notation.

0.884

hope this helps :) sorry I didn't include an explanation for a

p.s. i really need brainliest :)

Answer:

Step-by-step explanation:

"The capture-recapture of individually distinctive signature whistles has not been attempted before," says the paper's senior author Dr Tess Gridley, Co-Director of Sea Search and the Namibian Dolphin Project and a postdoctoral fellow in the Department of Botany and Zoology at SU. "The dolphins use these sounds throughout life and each has its own unique whistle. Therefore, by recording signature whistles over time and in different places we can calculate where animals are moving to and how many animals there are in a population."

Working with Dr Simon Elwen of Stellenbosch University, the Namibian Dolphin Project has been researching Namibia's resident bottlenose dolphins for the past 12 years, and built up a catalogue of more than 55 signature whistles dating back to 2009.

This particular study was led by Emma Longden, who began the project during her BSc (Hons) Marine Biology degree at the University of Plymouth. As an undergraduate, Emma completed an internship with the Namibia Dolphin Project for a month in 2016, and returned again in 2018 to complete work on the mark-recapture project.

She analysed more than 4000 hours of acoustic data from four hydrophones positioned along the coast south and north of Walvis Bay, Namibia, during the first six months of 2016.

All in all, they identified 204 acoustic encounters, 50 of which contained signature whistle types. From these encounters, 53 signature whistle types were identified; 40 were in an existing catalogue developed in 2014 for the Walvis Bay bottlenose dolphin population, and 13 were newly identified. Of the 53 signature whistle types identified, 43% were captured only once, whereas the majority (57%) were recaptured twice or more.

"One of the great things about bioacoustics is that you can leave a hydrophone in the water for weeks at a time and collect so much data without interfering with the lives of the animals you are studying," says Emma, whose work on the project was also supervised by Dr Clare Embling, Associate Professor of Marine Ecology at the University of Plymouth.

Dr Embling added: "This work is incredibly important as it allows us to track and count the number of dolphins in small vulnerable populations. It builds on our previous research looking at the impacts of noise on marine organisms and monitoring vulnerable marine mammal populations. It also showcases the fantastic level of research that our marine biology students are able to achieve, and the opportunities available to them through our partnerships with conservation organisations such as the Namibia Dolphin Project and the Ocean Giants Trust."

Future research includes the work undertaken by PhD student Sasha Dines from Stellenbosch University to further refine the technique to better understand the population of endangered humpback dolphins in South Africa. Another PhD student, Jack Fearey from the University of Cape Town, is continuing to conduct research along the Namibian Coast.

Answer:

A. 0

Step-by-step explanation:

use discriminant. discriminant value is negative so 0 solutions

k=6

have an amazing day bye!

Answer:

Hello! k = 6

Step-by-step explanation:

40 + 90 = 130 so our last angle must be 50 sense this will add up to 180 so k = 6 because 7 x 6 = 42 and 42 + 8 = 50 so answer 6

Answer:

22 units

Step-by-step explanation:

Answer:

The answer would therefore be 'x=18'.

Answer:

Step-by-step explanation:

7/7

Answer:

x = 30

Step-by-step explanation:

Answer:

1/81

Step-by-step explanation:

You just tap the calculator