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#176 2008-12-28 02:05:02

ganesh
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Re: Brain Teasers

#86. Find the value of

.


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#177 2008-12-28 15:56:38

careless25
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Registered: 2008-07-24
Posts: 555

Re: Brain Teasers

i feel like these were 2 easy for me ganesh. I like patterns and like to solve them, if you have more pls post. tongue

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#178 2008-12-28 16:03:32

careless25
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Posts: 555

Re: Brain Teasers

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#179 2008-12-28 16:27:51

ganesh
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Re: Brain Teasers

Answers to #79 and #81, #82, #83, #84, and #85.
Answer to #81 is correct, Answers to #82, #83, #84, and #85 are all correct.
Please check your answer to #79 again!

Your performance......

xln3.jpg

As required by you in post #177, I shall post more of these soon smile


Character is who you are when no one is looking.

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#180 2008-12-29 01:32:15

ganesh
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Re: Brain Teasers

careless25, these questions are posted based on your post #177:- smile

Find the wrong number in the series in the series of numbers given below:-

#87. 6, 12, 30, 84, 248, 732

#88. 4, 6, 24, 48, 144, 288

#89. 3, 8, 18, 36, 73, 148

#90. 1, 2, 6, 12, 36, 70, 216

#91. 10240, 2560, 640, 140, 40, 10

#92. 2, 9, 45, 303, 1815, 10887, 65319

#93. 5, 10, 47, 136, 680, 2026, 10127

#94. 30, 90, 180, 540, 1080, 2160, 6480

#95. 3, 9, 23, 51, 115, 241, 495

#96. 625, 275, 375, 75, 225, 45, 135

#97. 12, 13, 18, 20, 24, 28, 30

#98. 57, 70, 84, 97, 110, 124, 138

#99. 32, 34, 48, 52, 64, 68, 80

#100. 720, 120, 24, 8, 2, 1, 1

#101. 5, 27, 61, 122, 213, 340, 509


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#181 2008-12-29 02:26:21

ganesh
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Re: Brain Teasers

#102. Three pipes A, B, and C can fill a tank in 12, 15, and 20 hours respectively. If A is open all the time and B and C are open for one hour each alternately, in what time would the tank be full?


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#182 2008-12-29 16:51:39

ganesh
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Re: Brain Teasers

#103. Out of five questions in a question paper, one-twentieth of the students answer all the questions, and one-twentieth of them answer none. Of the rest, one-fourth answer four questions and one-fifth answered one question only. If 24½ % of the total number of students answered three question, what is the total number of students who appeared for the test?


Character is who you are when no one is looking.

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#183 2008-12-29 18:39:13

ganesh
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Re: Brain Teasers

Complete the series:-

#104. 16, 33, 65, 131, 261, ____

#105. 2, 6, 12, 20, 30, 42, 56, ____

#106. 8, 24, 12, 36, 18, 54, ____

#107. 2, 5, 9, 19, 37, ____

#108. 2197, 1331, 343, 125, 27, ____


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#184 2008-12-30 04:43:08

careless25
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Registered: 2008-07-24
Posts: 555

Re: Brain Teasers


A bit more challenging!!
Thats it for now, i will solve more later.up
Thx again,
C25

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#185 2008-12-30 18:28:06

ganesh
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Posts: 13,224

Re: Brain Teasers

Answers to #87, #88, #89, #90, #91, and #92:-
All answers other than #90 correct. That is five out of six correct.
Regarding #90,
#90. 1, 2, 6, 12, 36, 70, 216
The pattern is 1st number multiplied by 2, the second number multiplied by 3, the third number multiplied by 2, the fourth number multiplied by 3 and so on. Hence, 70 is the wrong number in the series.
Your performance has been excellent.
wd2.jpg


Character is who you are when no one is looking.

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#186 2008-12-30 19:25:04

ganesh
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Re: Brain Teasers

Complete the series:-

#109. 16, 13, 17, 12, 18, 11, ___.

#110. 3, 10, 29, 66, 127, ____.

#111. 1, 5, 13, 25, 41, _____.

#112. 99, 98, 94, 85, 69, 44, ____.

#113. 49, 51, 54, 27, 9, 11, 14, ____.

#114.

.

#115. 6.75, 4.5, 3, ____.


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#187 2008-12-31 23:04:55

ganesh
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Re: Brain Teasers

#116. Complete the series:
1, 4, 14, 45, 139, 422, _____.

#117. Complete the series:
5, 9, 16, 29, 54, 103, _____.

#118. In a division, the divisor is ten times the quotient and five times the remainder. if the remainder is 46, determine the dividend.

#119. Find the least number which on being divided by 5, 6, 8, 9, and 12 leaves a remainder of 1 in each case but leaves no remainder when divided by 13?

#120. Four natural numbers, when added three at a time give the sums of 180, 197, 208 and 222. Find the numbers.


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#188 2009-01-01 03:13:55

ganesh
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Re: Brain Teasers

#121. A contractor undertakes to do a certain job in 45 days and employs 15 persons for it. At the end of 36 days, he realizes the work is only half done. How many extra persons should he now employ to finish the work in time?


Character is who you are when no one is looking.

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#189 2009-01-01 04:14:11

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

Re: Brain Teasers


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

A: Click here for answer.

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#190 2009-01-01 17:02:03

ganesh
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Re: Brain Teasers

Answer to #121:
You are perfectly right, Janefairfax!
xln6.jpg


Character is who you are when no one is looking.

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#191 2009-01-01 17:14:45

ganesh
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Re: Brain Teasers

#122. The distance between two places X and Y is 60 kilometers. Two persons A and B start from X towards Y at the same time. The speed of B is 4 kilometers per hour less than that of A. A reaches Y, returns at once and meets B at a distance of 12 kilometers from Y. What is the speed of B?


Character is who you are when no one is looking.

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#192 2009-01-01 18:30:59

ganesh
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Re: Brain Teasers

#123. A wrist-watch is sold at a profit of 20%. If both the cost price and the selling price are were decreased by $100, the profit would have been 5% more. What is the original cost price of the watch?


Character is who you are when no one is looking.

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#193 2009-01-02 02:36:54

ganesh
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Registered: 2005-06-28
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Re: Brain Teasers

#124. If the sum of two numbers be multiplied by each separately, the products obtained are 2418 and 3666. What are the numbers?


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#194 2009-01-02 02:49:20

ganesh
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Registered: 2005-06-28
Posts: 13,224

Re: Brain Teasers

#125. What is the value of


if
?


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#195 2009-01-02 16:49:11

ganesh
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Posts: 13,224

Re: Brain Teasers

#126. A solid is in the form of a right circular cylinder with hemispherical ends. the total height of the solid is 70 centimeters. The diameter of the cylinder is one-fourth its height. Find the volume of the solid.

#127. To do a certain piece of work, B takes four times as long as A and C together and C takes three times as long as A and B together. if all of them working together complete the work in 12 days, how long would C alone take to do the work?

#128. 3 glasses A, B, and C whose capacities are in the ratio 1:2:3 respectively are mixtures of acid and water. The ratios of acid to water in A, B, and C are 1:5, 3:5, and 5:7 respectively. The contents of these glasses are emptied into a single vessel. What is the ratio of acid to water in the vessel?

#129. Water flows at the rate of 10 meters per minute through a cylindrical pipe whose internal radius is 0.5 centimeter. How long would it take to fill a conical vessel whose radius at the top is 20 centimeters and depth is 21 centimeters?

#130. The average score of girls in a Mathematics test is 73 and that of the boys is 71. The average score of both boys and girls together is 71.8. Find the percentages of the number of girls and the number of boys who appeared in the test.


Character is who you are when no one is looking.

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#196 2009-01-03 02:09:36

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

Re: Brain Teasers


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

A: Click here for answer.

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#197 2009-01-03 02:29:35

ganesh
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Registered: 2005-06-28
Posts: 13,224

Re: Brain Teasers

Answer to #125:-
Correct again, JaneFairfax!!!
wd5001.jpg


Character is who you are when no one is looking.

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#198 2009-01-03 10:21:31

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

Re: Brain Teasers


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

A: Click here for answer.

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#199 2009-01-03 17:29:24

ganesh
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Registered: 2005-06-28
Posts: 13,224

Re: Brain Teasers

Answer to #122:-
Perfectly right, Janefairfax!
grtjb9.jpg


Character is who you are when no one is looking.

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#200 2009-01-03 17:45:16

ganesh
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Registered: 2005-06-28
Posts: 13,224

Re: Brain Teasers

#131. What is the value of of


where
?

#132. 8 + 88 + 888 + 8888 + 88888 + ........ n terms = ?


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