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

ganesh
Registered: 2005-06-28
Posts: 26,826

### Re: Brain Teasers

#86. Find 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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## #177 2008-12-28 15:56:38

careless25
Real Member
Registered: 2008-07-24
Posts: 560

### 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.

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

careless25
Real Member
Registered: 2008-07-24
Posts: 560

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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.

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

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### Re: Brain Teasers

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

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

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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?

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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?

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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, ____

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

careless25
Real Member
Registered: 2008-07-24
Posts: 560

### Re: Brain Teasers

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

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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.

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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, ____.

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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.

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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?

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

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

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### Re: Brain Teasers

You are perfectly right, Janefairfax!

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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?

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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?

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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?

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### Re: Brain Teasers

#125. What is the value of

if
?

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### 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.

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

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

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### Re: Brain Teasers

Correct again, JaneFairfax!!!

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

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

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### Re: Brain Teasers

Perfectly right, Janefairfax!

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

ganesh
Registered: 2005-06-28
Posts: 26,826

### Re: Brain Teasers

#131. What is the value of of

where
?

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

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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