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All of you children and teen's and of course young adult's are wrong. I've been in the teaching district for all kinds of math since I was in my twenties. I work at four different universities. Princeton University, Arizona State University, Washington State University, and lastly New York University. Everyone of you whom have answered this question are misunderstood that the question for 'How much tax would be on 113.98 at 9%?' Well simply do the calculations. Most of you have it others, well need to stay in school or go back to school. I'm almost 65 this year and from all my years in working in the math department, math is just as if you were to tie your shoes. Hardest math I've ever done in my day's was the known math. Rocket science! Now it's simple. So here, instead of myself giving out the answer, let's take it step by step so this way you can get a better and more precise understanding for the well being of your sake. Would anyone prefer the help?

GuestDec 5, 2013

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I knw i makes me mad dde. Like 4real tho, ppl just view the ques. buh, nvr answr thm anymore?

GuestDec 5, 2013

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Well Jedithious, We are always welcoming and friendly....hmmm, well most of us on here So you're very welcome my friend ! Anyways, if you need anything name the title of your forum my name if you want to talk to me :p Or need my help in particular and I'll try my best to get back to you Thanks, I love meeting and helping out new people

GuestDec 5, 2013

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She said " Hello how are you? My name is samantha, what is your name..?" lol :p

GuestDec 5, 2013

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Yes thank you. I am sorry for the confusion, it's because that's how my brother wrote it then said his teacher wrote it the same way so I was confused myself as well. Thank you though melody

GuestDec 5, 2013

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Oh my goodness ! Thank you guy's so very much ! So I won the bet from the help of you lovely ladies & or gentlemen <3

GuestDec 5, 2013

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without parenthesis !

GuestDec 5, 2013

+118742

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op een intergalactische missie met een snelheid van 30000 km is men alle contact met de aarde verloren, hoe berekend men de weg terug als men 10 lichtjaren van de aarde verwijderd is en om de hoeveel tijd zal men de graden moeten her aanpassen om op welk tijdstip terug te zijn? vraag 2 hoeveel ouder zal men hier op aarde zijn als ze terug zijn en welke leeftijd zullen zij hebben, graag de berekeningen erbij aub, mvg, dank u ,julles

Translated Dutch to English by Bing

On an intergalactic mission with a speed of 30000 km one lost all contact with the Earth, is how one calculated the way back if one 10 light years from Earth has been removed and to how much time will one have to re adjust the degrees at any time be back?
Question 2: How many older one will here on Earth as they are back and what age they will have,
I'd like the calculations there please, mvg,
thank you, Julles
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So Julles do you mean:
You are traveling at 30000km.
How long will it take to travel 10 light years?

My problem is that 30000km is not a speed. You need 'per hour' or 'per second' or 'per some other period of time' to make it into a speed.

Bing Translation
Bing vertaling

Dus Julles doen bedoelt je:
U reist op 30000km.
Hoe lang duurt het om te reizen licht komende jaren van 10?

Mijn probleem is dat 30000km is niet een snelheid. U moet 'per uur' of 'per seconde' of 'per bepaalde periode van tijd' te maken in een snelheid.

MelodyDec 5, 2013

+118742

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Calc ellipse major axis knowing minor axis and angle of 30 deg.

What angle is 30degrees?

MelodyDec 5, 2013

+118742

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A train is moving a constant velocity. Inside the train, you hold a rock next to your shoulder and let it go, The rock hits the floor.
a) Behind your back b) exactly below your hand c) ahead of your hand

A stone is in free fall downward. At this moment, it's falling at 45 m/s. A second later its downward speed will be about
a)55 m/s b)45 m/s c) 35 m/s d) There's no way to tell

Now, suppose you use slingshot upward with a speed of 25 m/s. two seconds later its speed will be about
a) 50 m/s b)45 m/s c)5 m/s d)12.5 m/s

Hi Olive,
Are you supposed to be using physics formulas, calculus or educated guessing?
Special has certainly got the right ideas.
a) You and the book have initially got the same speed. The books speed doesn't change just because it is dropped (unless there is a big wind or something) so it should drop near your feet.
My prediction is the same as Special's
b) As Special said, it'll get faster . Using calculus I got 54.8m/s ²
c) I am assuming that initially the stone is going straight up. Using calculus I know that after 2 seconds the stone is still going up and the speed is about 5.4m/s
None of these answers take into account air resistance or wind or anything like that.

I hope that you didn't mind me posting this after your answer Special, your answers were correct.

MelodyDec 5, 2013

+118742

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a single die is rolled 6 times. "Success" is getting a 3 or a 5. "Failure" is getting anything else. What is the probability of achieving exactly 2 successes in the 6 rolls?

P(success)=2/6 = 1/3
P(failure) = 4/6 = 2/3
number of ways you can get 2 successes and 4 failures in 6 rolls is ⁶C ₂ ( ⁶C ₄ gives exactly the same answer)

P(2 successes) = 6C2 * (1/3) ² * (2/3) ⁴

= 15 * 1/9 * 16/81

= 80/243

MelodyDec 5, 2013

+118742

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:a=10 b=20 c=6
v=πa(ab+c*c)

v = pi * 10 * (10*20 + 6*6)
v = 10 * pi * 236
v = 2360pi
v = 7414.159 (to 3 decimal places)

MelodyDec 5, 2013

+118742

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3x+6y=-8
Our unknown friend certainly gave you the correct answer, this is a little explanation
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when x=0
6y=-8
y=-4/3 this is the y intercept
--------------------------------
when y=0
3x=-8
x=-8/3 this is the x intercept

MelodyDec 5, 2013

+118742

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suppose that p is invested in a savings account in which interest k, is compounded continuously at 3% per year. What is the exponential growth function in terms of P and 0.03?
b) if $6000 is invested what is the balance after 4 years?
c) when will an investment of $6000 double itself?
------------------------------
I am going to re-word your question a little.
Suppose that P is invested in a savings account at 3% p.a. interest, compounding annually. (the interest is added at the end of each year)
I am going to call the future value S (in my experience S is the standard letter used for future value.)
I am going to let the number of years invested be n

a) S = P * 1.03 ⁿ

b) S = 6000 * 1.03 ⁴
you can finish this one.

c) 2P = P * 1.03 ⁿ
2 = 1.03 ⁿ
log 2 = log 1.03 ⁿ
log 2 = n*log1.03
n = log2 / log1.03
n = 23.449 years
Since the interest is added at the end of the year it will be doubled in 24 years (It will be a little more than double at this time)

MelodyDec 5, 2013

+118742

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what is the solution of
y=8x+4 y=2(x+5)

you have to put

8x + 4 = 2(x + 5)
solve for x
then substitute the x value into one of the original equations and solve for y

MelodyDec 5, 2013

+118742

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Dax opens a new box of chocolate. There is a total of 60 pieces inside of 3 types of flavours: white, milk, and dark chocolate. 30% is white, 60% is milk, and 10% is dark. Dax eats 2 chocolates how many pieces of each chocolate are left in the box?

That would depend on which type of chocolates that Dax ate.

MelodyDec 5, 2013

+118742

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2+4+6+8+......+200=

This is an arithmetic progression AP for short

a = 2
d=2
n=100
s _n= n/2[a+T ₁₀₀]

sum = 50(2+200) = 50*202 = 10100

MelodyDec 5, 2013

+118742

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Solve 12cosx-5sinx=4 for 0<x<90

You have to divide everything by sqrt(12 ²+5 ²) = 13
so
12/13 * cosx - 5/13 * sinx = 4/13

The reason that this is useful is that 5, 12, 13 is a pythagorean triad. (Draw the triangle, it will help you understand)
And I know that

sin(theta)cos(x) - cos(theta)sin(x) = sin(theta - x)
so
If sin(theta)=12/13, then cos(theta) has to equal 5/13 (put theta on your triangle and convince yourself that this is true)

also theta = sin ^-1(12/13) = 67.380 degrees
NOW

12/13 * cosx - 5/13 * sinx = 4/13

sin(67.380)*cosx - cos(67.380)*sinx = 4/13

sin (67.380 - x) = 4/13

sin ^-1(4/13) = 67.380 - x

17.920 = 67.380 - x

x = 67.380 - 17.920

x = 49.46 = 49 degrees (to the nearest degree.)

MelodyDec 5, 2013

+118742

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what is the answer and what are the steps
(7+x)/3=8

multiply both sides by 3
then
subtract 7 off both sides.

MelodyDec 5, 2013

+118742

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By putin in the angle and then pressing inv tan

MelodyDec 5, 2013

+118742

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It is probably more important that you remember why!

Remember

cosine is adjacent / hyptotenuse

sine is opposite over hypotenuse

The hyptoenuse HAS to be the longest side so sine and cosine have to be between 0 and 1 (for first quadrant)
In the other quadrants only the sign changes.

So sine and cos have to be between -1 and 1.

Hope that helps Special.

MelodyDec 5, 2013

+118742

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It is probably more important that you remember why!

Remember

cosine is adjacent / hyptotenuse

sine is opposite over hypotenuse

The hyptoenuse HAS to be the longest side so sine and cosine have to be between 0 and 1 (for first quadrant)
In the other quadrants only the sign changes.

So sine and cos have to be between -1 and 1.

Hope that helps Special.

MelodyDec 5, 2013

+118742

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I've never had a calulator that allows this.
If I wanted to put the exact value of 0.333333.... in I would put in 1/3

A question for Special,
What kind of calculator do you have?
Melody.

MelodyDec 5, 2013

+118742

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What is the domain of (fg)(x)?

Your question doesn't make sense so I assume this notation is new to you.

You probably mean the domain f(g(x)) and you got it from a different question.

The domain is all the values that x is allowed to be.

(The range would be all the values that y is allowed to be.)

I hope this helps. You can ask questions like this on the back of other posts if you want to.

MelodyDec 5, 2013

+6

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Thank you SOOOO MUCH!!

taylorb56Dec 5, 2013

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