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#201 2009-01-03 23:52:50
- JaneFairfax
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Re: Brain Teasers
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#202 2009-01-04 00:03:10
- Jai Ganesh
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Re: Brain Teasers
Answer to #131:-
Absolutely right, Janefairfax!
#132. A polygon has 44 diagonals. How many sides does it have?
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#203 2009-01-04 00:22:09
- JaneFairfax
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Re: Brain Teasers
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#204 2009-01-04 01:08:15
- Jai Ganesh
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Re: Brain Teasers
Answer to #132:
You are correct, Janefairfax!
#133. There are 7 men and 3 ladies. Find the number of ways in which a committee of 6 prsons can be formed if the committee is to have atleast 2 ladies.
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#205 2009-01-04 01:53:52
- JaneFairfax
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Re: Brain Teasers
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#206 2009-01-04 03:11:57
- Jai Ganesh
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Re: Brain Teasers
Answer to #133:-
You are correct, JaneFairfax!
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#207 2009-01-04 04:44:11
- JaneFairfax
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Re: Brain Teasers
Last edited by JaneFairfax (2009-01-04 04:45:40)
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#208 2009-01-05 01:55:08
- Jai Ganesh
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Re: Brain Teasers
Answer to #127:-
Correct, JaneFairfax!
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#209 2009-01-05 03:08:45
- Jai Ganesh
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Re: Brain Teasers
#133. The number of rectangles excluding squares from a rectangle of 9 x 6 size is _______.
#134. Out of 18 points in a plane, no three points are in the same straight line except five points which are collinear. Find
(i) the number of straight lines
(ii) the number of triangles which can be formed by joining them.
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#210 2009-01-05 03:18:27
- Jai Ganesh
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Re: Brain Teasers
#135. Let
.Add all the digits of the resulting value, assume you get a value n.
Add all the digits of n, assume you get a value n'.
Add all the digits of n', assume you get n''.
Continue this process until you get a single digit.
What is the number you would get?
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#211 2009-01-06 08:19:07
- careless25
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Re: Brain Teasers
Last edited by careless25 (2009-01-06 08:19:17)
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#212 2009-01-06 08:41:50
- careless25
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#213 2009-01-06 08:48:03
- JaneFairfax
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#214 2009-01-06 08:50:03
- careless25
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#215 2009-01-06 12:04:38
- JaneFairfax
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#216 2009-01-06 20:58:41
- Jai Ganesh
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Re: Brain Teasers
Answers to #104, #105, #106, #107, and #108:
All correct, other than #108.
careless25,
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#217 2009-01-06 21:22:14
- Jai Ganesh
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Re: Brain Teasers
Answers to OOO : #94, #95, #96, #97, #98, #99, #100, and #101:
careless25,
Answers to #94, #98, #99, and #100 : Correct!
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#218 2009-01-06 21:29:56
- Jai Ganesh
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Re: Brain Teasers
Answer to #135:-
Correct, JaneFairfax!
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#219 2009-01-06 21:46:42
- Jai Ganesh
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Re: Brain Teasers
Answers to #109, #110, #111, #112, #113, #114, and #115:-
careless25, the answers to #109, #111, #112, and #113 are correct.
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#220 2009-01-06 21:55:50
- Jai Ganesh
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Re: Brain Teasers
Answer to #124:
You are correct, JaneFairfax!
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#221 2009-01-07 02:08:27
- careless25
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Re: Brain Teasers
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#222 2009-01-07 02:37:24
- Jai Ganesh
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Re: Brain Teasers
careless25,
I thought from that point of view for a second, but didn't go any further! That was my mistake!
Your answer too is perfectly logical and fits in.
Good thought! Well done!!!
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#223 2009-01-07 19:58:04
- Jai Ganesh
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Re: Brain Teasers
Complete the series:-
#136. 1, 6, 36, 216, ____
#137. 1973, 1979, 1987, 1993, 1997, 1999, ______.
#138. 5, 10, 13, 26, 29, 58, 61, _______.
#139. 11, 13, 17, 19, 23, 29, 31, 37, 41, _____.
#140. 3, 7, 6, 5, 9, 3, 12, 1, 15, ______.
#141. 11, 24, 67, 122, 219, _____.
#142. 64, 32, 35, 5, 22, 11, 14, _____.
#143. 0, 6, 24, 60, 120, ______.
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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#224 2009-01-08 03:49:09
- JaneFairfax
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Re: Brain Teasers
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#225 2009-01-08 08:20:41
- careless25
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Re: Brain Teasers
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