Melody

Edit:   The program seems to have taken a dislike to me using a less thant sign for a angle sign.

Chunks of my solution have disappeared.    Bummer!

Maybe you can fill in some of the blanks yourself.  The first part was easy.

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1)

becasue;

If two lines are cut by a tranversal and the resulting co-interior anges are supplementary then the 2 lines must be parallel.

2)

L3 is parallel to L1

and QT is perpendicular to L3

so QT is perpendicular to L1 s

so angle PQT  = 90 degrees.

RP is perpendicular to QT   given

so     

triangle QSP and triangle RPS are similar  (2 equal angles)

so the the third angles must also be equal   

so   

so   

so  QT is perpendicular to L2

.

f is said to be incresaing whenever the gradient of the tangent is positive.  When is that?

Hi IMB   (I am bad ... )

Welcome to the Web2.0calc forum!

Give yourself a point  

Thanks  for the confirmation Tiggsy.  

And thanks guest asker for interacting so nicely :)

Ahr Tiggsy is answering.  He must have seen something that i overlooked.  

You are very welcome.  

Move onto your next question :)

A stick has a length of  units. The stick is then broken at two points, chosen at random. What is the probability that all three resulting pieces are shorter than  units?

First use contour mapping to graph the sample space.

Let the lengths be  x, y-x  and 5-y   

they add up to 5.

I know that  each of thise is between 0 and 5 units

0

0

0

x

y>x      (2)

0<5-y<5

-5<-y<0

0

Here is your sample space.  Every possible outcome is in there.

Now you have to graph the favourable sample space.  LOL you did not proof read your question!  

You want people to answer you.  You even tell an answerer that their answer is wrong.

Of course it is wrong, there is no question.  What a waste of our time. 

My interpretation of the question

A coin is chosen and not returned BUT a dummy coin is thrown into the mix so that there will still be 10 coins to chose from

Then a second coint is chosen.  What is the probablility that this second coin is an old one.

I have answered this question correctly.

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Perhaps you are answering a different interpretation of the question ? I mean maybe you are trying to answering the intended question but it is not actually the question asked.

I think this maybe what you are trying to answer:

A coin purse has 3 OLD one-peso coins and 7 NEW one-peso coins. Suppose you randomly pick a coin and upon selecting, a dummy silver coin is placed on the purse as a placeholder for the coin you picked. If a second and third coin is picked from the coin purse, what is the probability that the second third coin is an OLD one peso? 

Does that sound right to you?  there are 3 picks so that is  2^3 = 8 outcomes.

I did look at this but I still got  27/100

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Unless you can think of a third interpretation of the question then I think none of those choices are correct.

Plus I do ot understand your working at all.   

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Perhaps you should move onto onother of you questions as I really believe that this one is a dud.  

Thanks Alan,

I still don't  get it but that doesn't matter.  (I have a calculator :/)

Hopefully the shadow will understand.