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#201 2007-02-18 17:42:40

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

Re: 10 second questions

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#202 2007-02-19 02:46:10

ganesh
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Registered: 2005-06-28
Posts: 12,962

Re: 10 second questions

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?


Character is who you are when no one is looking.

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#203 2007-02-19 03:02:43

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

Re: 10 second questions

Are you sure about #132?

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#204 2007-02-19 03:25:45

ganesh
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Registered: 2005-06-28
Posts: 12,962

Re: 10 second questions

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

?


Character is who you are when no one is looking.

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#205 2007-02-19 03:52:37

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

Re: 10 second questions

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#206 2007-02-19 03:58:41

ganesh
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Registered: 2005-06-28
Posts: 12,962

Re: 10 second questions

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!


Character is who you are when no one is looking.

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#207 2007-02-19 04:01:24

kylekatarn
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Registered: 2005-07-24
Posts: 445

Re: 10 second questions

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

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#208 2007-02-19 04:05:47

ganesh
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Registered: 2005-06-28
Posts: 12,962

Re: 10 second questions

Excellent, kylekatarn!
It would have been a good enough answer if someone had replied 57.
Well done!


Character is who you are when no one is looking.

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#209 2007-02-19 04:09:04

kylekatarn
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Registered: 2005-07-24
Posts: 445

Re: 10 second questions

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:)
smile

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

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#210 2007-02-19 04:32:45

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

Re: 10 second questions

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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#211 2007-02-19 06:46:45

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

Re: 10 second questions

136. A certain sum of money doubles in 10 years at simple
interest. What is the rate of interest?

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#212 2007-02-19 07:44:29

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

Re: 10 second questions

139. If


what is the value of n?

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#213 2007-02-19 16:29:21

ganesh
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Registered: 2005-06-28
Posts: 12,962

Re: 10 second questions

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.)


Character is who you are when no one is looking.

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#214 2007-02-19 20:52:05

ganesh
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Registered: 2005-06-28
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Re: 10 second questions

145. How many cubic inches make a cubic foot?

146. How many square yards make a square mile?


Character is who you are when no one is looking.

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#215 2007-02-19 22:39:42

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

Re: 10 second questions

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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#216 2007-02-20 01:17:06

ganesh
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Registered: 2005-06-28
Posts: 12,962

Re: 10 second questions

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


Character is who you are when no one is looking.

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#217 2007-02-20 01:23:38

ganesh
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Registered: 2005-06-28
Posts: 12,962

Re: 10 second questions

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?


Character is who you are when no one is looking.

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#218 2007-02-22 16:51:24

ganesh
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Registered: 2005-06-28
Posts: 12,962

Re: 10 second questions

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?


Character is who you are when no one is looking.

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#219 2007-02-23 12:54:41

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

Re: 10 second questions

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


Q: Who wrote the novels Mrs Dalloway and To the Lighthouse?

A: Click here for answer.

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#220 2007-02-23 17:02:55

ganesh
Moderator
Registered: 2005-06-28
Posts: 12,962

Re: 10 second questions

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


Character is who you are when no one is looking.

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#221 2007-02-27 16:30:19

ganesh
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Registered: 2005-06-28
Posts: 12,962

Re: 10 second questions

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, ....?


Character is who you are when no one is looking.

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#222 2007-02-28 02:15:56

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

Re: 10 second questions


Why did the vector cross the road?
It wanted to be normal.

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#223 2007-02-28 03:13:27

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

Re: 10 second questions

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


Bad speling makes me [sic]

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#224 2007-02-28 10:00:55

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

Re: 10 second questions

Dross wrote:

  wink


Q: Who wrote the novels Mrs Dalloway and To the Lighthouse?

A: Click here for answer.

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#225 2007-02-28 11:19:50

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

Re: 10 second questions

true


I hate people who hate people.
most people make mistakes, butt not me! smile smile
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