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**pi man****Member**- Registered: 2006-07-06
- Posts: 251

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 23,059

Very well done, kylekatarn!

You are correct!

Excellent, pi man!

But for your answers to #132 and #136, your answers are all correct! Very well done! Please try these questions again!

139. If

what is the value of n?

140. Which of the four is the greatest?

7/22, 11/30, 12/31 or 4/11?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**pi man****Member**- Registered: 2006-07-06
- Posts: 251

Are you sure about #132?

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**ganesh****Administrator**- Registered: 2005-06-28
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pi man,

this happens to me quite often!

Once, while disbursing the salary, instead of putting Rs.12,500/- in a cover, I put Rs.15,200/- and I was wondering where Rs.2,700/- had vanished! I kept checking the covers, but I was unable to find out where I'd gone wrong!

It was a big relief when the person for whom it was intended, counted the money, and returned the excess!

141. How many degrees is a radian approximately?

142. If 3tanθ=4, what is the value of

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**pi man****Member**- Registered: 2006-07-06
- Posts: 251

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 23,059

Very well done, pi man!

You are correct! The explanation and reasoning were interesting!

I use a simple technique.

To compare a/b and c/d, find the products ad and bc. ad would respresent a/b and bc would be for c/d.

If ad is greater, the first fraction is greater, and so on.

This way, be eliminating the lesser fractions, I'd reach the greatest!

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**kylekatarn****Member**- Registered: 2005-07-24
- Posts: 445

*Last edited by kylekatarn (2007-02-19 04:07:41)*

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 23,059

Excellent, kylekatarn!

It would have been a good enough answer if someone had replied 57.

Well done!

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**kylekatarn****Member**- Registered: 2005-07-24
- Posts: 445

thanks, you have here a nice set of exercises (from the beginning) , why don't you compile them into a small book? a pdf or something like that:)

*Last edited by kylekatarn (2007-02-19 04:09:30)*

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**pi man****Member**- Registered: 2006-07-06
- Posts: 251

Ganesh - I agree with kylekatarn. Excellent work. Are you keeping track of which ones haven't been successfully answered? If so, maybe publish that list occasionally.

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**pi man****Member**- Registered: 2006-07-06
- Posts: 251

136. A certain sum of money doubles in 10 years at simple

interest. What is the rate of interest?

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**pi man****Member**- Registered: 2006-07-06
- Posts: 251

139. If

what is the value of n?

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 23,059

Thanks pi man and kylekatarn!

I am happy posting the problems here, I do occasionally check for the problems which haven't been answered. Often, during the weekend. I shall post the solutions.

Thank again!

137. pi man, you are calculating assuming the interest is paid as compound interest, the question clearly says simple interest is paid.

139. I had the US Centillion in my mind, the reason being, in most places in the world, the US notation is followed, barring UK and some European nations, where a billion is a million million and so on.

143. How many odd numbers between 1 and 1000 are divisble by 7?

144. How many perfect powers exist between 1 and 1000? (perfect squares, perfect cubes, perfect fourth powers, etc.)

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 23,059

145. How many cubic inches make a cubic foot?

146. How many square yards make a square mile?

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**mathsyperson****Moderator**- Registered: 2005-06-22
- Posts: 4,900

Pi man, the US Centillion is a million multiplied by a thousand 99 times. Or if you prefer, a thousand multipled by a thousand 100 times.

You can derive that by thinking about what they do to get from a million to a billion, then to a trillion, and so on.

Why did the vector cross the road?

It wanted to be normal.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 23,059

Excellent, mathsyperson! I wonder if 10 seconds would have been sufficient! it took me a little longer!

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 23,059

147. What would be the successive sum of all the digits (that is, the sum of the repeatedly, until you get a single digit) of

148. What digit would

end in?Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 23,059

149. What is the lenght of the longest rod that can be placed inside a room 10m long, 10 m wide and 10 m high?

150. What is the probability of getting two black kings when two cards are drawn at random from a well shuffled pack of 52 cards, without replacement?

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**JaneFairfax****Member**- Registered: 2007-02-23
- Posts: 6,868

*Last edited by JaneFairfax (2007-02-23 13:25:01)*

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 23,059

**Excellent, JaneFairfax!All your answers are correct!!!**

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 23,059

151. An equilateral triangle is formed by joining the

middle points of the sides of a given equilateral triangle. A

third equilateral triangle is formed inside the second

equilateral triangle in the same way. If the process continues

indefinitely, then what is the sum of areas of all such triangles when

the side of the first triangle is 16 cm is?

152. What is the sum of first 100 terms which are

common to both the progressions

17, 21, 25, ... and 16, 21, 26, ....?

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**mathsyperson****Moderator**- Registered: 2005-06-22
- Posts: 4,900

Why did the vector cross the road?

It wanted to be normal.

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**Dross****Member**- Registered: 2006-08-24
- Posts: 325

*Last edited by Dross (2007-02-28 04:31:22)*

Bad speling makes me [sic]

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**JaneFairfax****Member**- Registered: 2007-02-23
- Posts: 6,868

Dross wrote:

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**power man****Member**- Registered: 2006-12-26
- Posts: 160

true

I hate people who hate people.

most people make mistakes, butt not me!

why is it when you are writing something important you run out of spa

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