All Answers 358087 Answers

Hi Mellie we were just chatting. My computer won't work so I can't log in, so I can't send a private message to anyone. So yeah I did this! 😉

There is a probability of 1/8 that the number 1 will show.  

There is a probability of 1/8 that the number 2 will show.

 and so on until you get to:

There is a probability of 1/8 that the number 8 will show.

The expected value is the sum of (probability that the number will show)*(the number) or in this case:

(1/8)*1 + (1/8)*2 + (1/8)*3 + ... +(1/8)*8

or

(1/8)*(1  2 + 3 + 4 + 5 + 6 + 7 + 8) = (1/8)*36 = 4.5

We can use a shortcut to sum the numbers 1 through 8.  It is given by 8*(8+1)/2.

Does this help?

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what?         

You could plot y = the quadratic, and see where it crosses the x-axis (where y = 0).  For example:

though, in the case of this example it is easy to see from the form of the equation that the roots are 0 and 7.

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Hi, what happened? 

Umm, I usually work with American dollars, but I'll roll with it.

You want to find 41 percent of 860 and subtract it from 860. 

Make a proportion:

x/860=41/100

Cross multiply:

860*41=35260

35260=100x

Divide both sides by 100 to get x alone. 

x=352.60

Now, we are not done yet.

Subtract your value of x from 860

860-352.60=507.40

Your final answer: £507.40

12 in=1 foot

Just multiply 1.3 by 12. I think...

$${\mathtt{1.3}}{\mathtt{\,\times\,}}{\mathtt{12}} = {\frac{{\mathtt{78}}}{{\mathtt{5}}}} = {\mathtt{15.6}}$$

I'm pretty sure that is correct, but I'm not very bright. I always make careless mistakes. 😁

No need to make a new post, but I agree

As you know, it is 19.

However, it SHOULD be 21!

yeah, positive x cause of imaginary numbers. also it works for any $${\sqrt[{{\mathtt{{\mathtt{n}}}}}]{{\mathtt{x}}}} = {\sqrt[{{\mathtt{\left({\mathtt{n}}{\mathtt{\,-\,}}{\mathtt{1}}\right)}}}]{{\frac{{\mathtt{x}}}{{\sqrt[{{\mathtt{{\mathtt{n}}}}}]{{\mathtt{x}}}}}}}}$$

I don't understand. Sorry Alan.

Half right!

If y = 2 then 2^x = 2 so x = 1 ok

But if y = -1 then you need 2^x = -1 and this is not possible in the real number domain.  When x is -1, 2^-1 = 1/2 not -1. 

2^x is always a positive number for x positive or negative. 

So the only valid solution here is x = 1

Put each value of x back into the original equation to check.

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Ya know, BJ, you're the nicest person who has an account on this website. I like you a lot! Thank you! 👗

Yes thanks, i found x as 1 or x as -1

were both doing it on John Cabot

That means the question should probably have been phrased to ask for the probability that Alex catches the train in order to avoid misinterpretation.

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i gotta do a project on the Age of Exploration. I have to make a posterboard. Titanium Rome is almost done with his, but he's too busy making YouTube videos (which are honestly horrible) and goofing off

You are doing ok so far.  Next step is to write 2^2x as (2^x)^2 then let y = 2^x so you have

y^2 - y - 2 = 0       (Taking each term in your last line to the other side first, so the y^2 term is positive)

This factors as 

(y + 1)(y - 2) = 0

Can you take it from here?

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hiya! how ya doing?

sin 30° = 1/2

cos 30° = (√3)/2

tan 30° = 1/√3 = (√3)/3

See what you can do with those.

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wait wat project? i just finished a project kinda like that :D

k, then son #3 is 10!

18.57417562100671

Each side has a probability of 1/8 of showing (assuming a fair die).  The expected value is one eighth of the sum of the numbers from 1 to 8 or (1/8)*8*9/2 = 9/2 = 4.5

(The sum of the integers from 1 to n is n(n+1)/2)

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