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## #126 2009-01-23 04:58:33

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

Both #78 and #80 are correct, JaneFairfax!

The questions were posted in a hurry, I didn't have the time to refer my online LaTeX guide. I didn't know it had to be done that way. The inconvenience caused is regretted.

#81. Find the point on the curve

at which the tangent is parallel to the x-axis.

#82. Show that the function

is increasing on R.

#83. Find the general solution of the differential equation

.

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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## #127 2009-01-23 11:52:08

JaneFairfax
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## #128 2009-01-23 18:41:30

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

Correct, 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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## #129 2009-01-24 03:54:38

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

#84. Prove that the logarithmic function is strictly increasing whenever it is defined.

#85. Find the dimensions and the perimter of a rectangle of area 96 square centimeters whose perimeter is the least.

#86. Find the general solution of the differential equation

.

#87. The bottom of a cuboidal swimming pool is 25 meters wide and 40 meters long. Water is pumped into the tank at the rate of 500 m³ per hour. Find the rate at which the water level is rising.

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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## #130 2009-01-24 04:32:36

JaneFairfax
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## #131 2009-01-24 04:41:50

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

Answers to #84, #85, #86, and #87:-
All correct, 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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## #132 2009-01-24 18:33:15

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

#88. The length of the circumference of a circle is equal to the length of the perimter of a triangle of equal sides and also equal to the perimter of a square. Which of the following is true if the areas of the circle, triangle and square are c, t, and s respectively?
(1) s > t > c
(2) c > t > s
(3) c > s > t
(4) s > c > t

#89. In Roman Numerals,
(a) what is the value of MDCCLXXXVII?
(b) what is the value of MCMXCIX?
(c) how is 1995 expressed?

#90. An intelligency agency forms a code of two distinct digits selected from 0, 1, 2, ,3, ....9 such tat the first digit of the code is non-zero. The code, handwritten on a slip, can however create misinterpretation when read upside down - for example, the code 91 may appear as 16. How many codes are there for which no such confusion would arise?

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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## #133 2009-01-25 03:39:20

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

#91. If a, a+2, a+4 are prime numbers where

, what is the number of values a can be given?

#92. A survey on a sample of 25 new cars being sold at a local automobile dealer was conducted to study which of the three popular facilities - air-conditioning, radio and power windows - were already installed. The survey found

3 had all the three facilities.

What is the number of cars that had none of these facilities?

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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## #134 2009-01-25 03:57:51

JaneFairfax
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Posts: 6,868

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## #135 2009-01-25 03:59:46

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

Correct, JaneFairfax! Good!

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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## #136 2009-01-25 04:29:57

JaneFairfax
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## #137 2009-01-25 19:26:46

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

Correct, 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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## #138 2009-01-26 00:15:09

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

### Re: 5 Star Questions

Can you give the list of digits that are potentially confusable, so that we can be sure we are playing the game by the same rules?

Last edited by JaneFairfax (2009-01-26 02:36:43)

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## #139 2009-01-26 02:33:43

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

Explanation to #90:
Please understand, I'd hate to be unfair and say someone's wrong without enough reason.
What makes you think that 11 or 88 read upside down would cause misinterpretation? They would still appear as 11 and 88 respectively. It was stated in the question 'the code, handwritten in a slip can however create misinterpretation when read upside down - for example, the code 91 may appear as 16'. Which means 1 is written as |. And

as
.

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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## #140 2009-01-26 02:39:19

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

### Re: 5 Star Questions

Then it was entirely my fault. Sorry.

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## #141 2009-01-26 02:58:23

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

#93. The salary of an employee is \$1,600. His expenditure on food, clothing, house rent and entermainment are represented by a pie chart making central angles 157.5°, 67.5°, 54°, and 36° respectively. What is his monthly saving?

#94. For any integer n, what is the argument of

?

#95. In a Geometric Progression, both the first term and the common ratio are

.
What is the magnitude of the
term of the Geometric Progression?

#96. If

, then 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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## #142 2009-01-26 13:27:13

JaneFairfax
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## #143 2009-01-26 17:11:32

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

Excellent!!!

Regarding #96, I guess you've made a minor mistake somewhere. Please try again.

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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## #144 2009-01-27 00:40:41

JaneFairfax
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## #145 2009-01-27 01:56:52

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

Correct, JaneFairfax!

#97. If

are the roots of the equation
, then what is the value of
?

#98. If

, then what is the value of
?

#99. If n is an integer other than a multiple of 3, then what is the value of

?

#100. If n is a multiple of 3, then 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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## #146 2009-01-27 03:26:50

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

### Re: 5 Star Questions

Last edited by JaneFairfax (2009-01-27 03:28:38)

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## #147 2009-01-27 03:34:18

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

You are correct, JaneFairfax!

#101. If

,
then, 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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## #148 2009-01-28 02:56:19

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

Perfect, 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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## #149 2009-01-28 02:59:36

ganesh
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Registered: 2005-06-28
Posts: 21,730

### Re: 5 Star Questions

#102. How many different nine digit numbers can be formed from the number 223355888 by rearranging its digits so that the odd digits occupy even positions?

#103. Five digit numbers are formed using 0, 1, 2, 3, and 4. How many numbers would be there in which atleast one digit is repeated?

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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## #150 2009-01-28 04:49:21

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