Melody

Are you guys from Flvs

I think maybe Britette means 

Florida Virtual School    :)

one way:

1*10^-1=

1*10^-1 = 0.1

ok NSM :)

CPhill is right.  Hectictar knows what she is talking about.

Please encourage her, and others, to explain answers more if you want/need  more explanation.

I would like this forum to not only teach maths but also teach people how to explain maths more effectively.  So if you do not understand then try and get the person who already answered to explain more.  Learning is more effective if it is interactive. :)

Plus, all answerers like return questions from the asker, it makes us feel appreciated and like someone is actually trying to learn from us and that is definitely what we want !    

If hectictar has answered your question/s then you should ask her to explain it more if that is what you want.  Do not forget to thank her. 

Hi Not so smart,

Maybe CPhill will do this for you becasue he is a sweety but you should look at the answers yourself.

If you think they may be wrong then you should ask questions.

If you do not have enough understanding to do this then the question is above you and you should just accept that you cannot do it.  If you take anyone's answer without fully understanding it and present it as homework done by you. That is just outright cheating!

I am not trying to be mean, I just want this forum to be used as a place people learn. Not as a place where people copy and learn nothing.

How lucky!  We all got the same answer :DD

Colouryellowblackred

Probability1/7??

Daniel has a bag of marbles. he has twice as many black marbles as red marbles. the rest are yellow. he is going to take a marble at random from the bag. yellow is 1/7 what is black and red probability?

P(yellow) = 1/7

so

P(red or black) = 6/7

and there are twice as many black as red so that must be 

P(red)=2/7

P(black)=4/7

Twenty-five percent of all automobiles undergoing an emissions inspection at a certain inspection station fail the inspection. 

(d) What is the probability that among 25 randomly selected cars, the number that pass is within 1 standard deviation of the mean value? 

I think this is a trick question.....

The number that are within 1 standard deviation of the mean in a normal distribution, which I think is assumed here, is always  68%

(2^2)^-2

\((2^2)^{-2}\\ =4^{-2}\\ =\frac{\color{blue}{1} *\color{black}4^{-2}}{1}\\ =\frac{\color{blue}{1} }{1*\color{black}4^{+2}}\\ =\frac{\color{blue}{1} }{\color{black}4^{2}}\\ =\frac{\color{blue}1 }{\color{black}16}\\ \)

What amount does a lottery winner have to pay into a savings account with an interest rate of 3.9% pa and then be able to withdraw 48,000 € for 25 years at the end of the year?

How much € should the amount be? (To the cent exactly)

withdraw 48000 at the end of every year of 25 years. Interest = 0.039

\(PV=48000*\frac{1-1.039^{-25}}{0.039}\)

48000*((1-1.039^-25)/0.039) = 757 848.95

sensible check:  25*48000 = 1 200 000  answer sounds ok.

So that is       757 848.95 euros