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#301 2009-02-06 01:06:17

Jai Ganesh
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Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#551. Two buses, one travelling towards North and the other towards East, leave the same place at the same time. The speed of one of the buses is greater than that of the other by 5 kilometers/hour. At the end of two hours, they are at a distance of 50 kilometers from each other. What is the speed of the slower bus in kilometers/hour?

#552. Ten men can finish a work in 10 days, whereas it takes 12 women to finish it in 10 days. If 15 men and 6 women work together, how many days would they take to complete the work?

#553. The speed of a boat in still water is 4 kilometers/hour and the speed of the current is 2 kilometers/hour. If the time taken by the boat to reach a certain point going upstream is 9 hours, what time would be taken to return to the starting point downstream?

#554. If the ages of P and R are added to twice the age of Q, the total is 59. If the ages of Q and R are added to thrice the age of P, the total is 68, and if the age of P is added to thrice the age of Q and thrice the age of R, the total is 108. What is the age of P?

#555. The length and breadth of a playground are 36 meters and 21 meters respectively. Poles are required to be fixed all along the boundary at a distance 3 meters apart. How many ploes would be required?


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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#302 2009-02-06 02:47:44

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#556. What is the least number that must be subtracted from 7186 to make it a perfect square?

#557. Find the twentieth term of the series 3, 7, 11, 15, ...... .

#558. The third term of a Geometric Progression is 36 and the sixth term is 972. What is the fifth term of the Geometric Progression?

#559. Find the sum of the first 10 terms of the Geometric Progression 3, 6, 12, 24, ..... .

#560. If a = 5 and b = -9, find the value of

.


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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#303 2009-02-07 02:34:02

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#561. The sum of four consecutive odd two-digit numbers, when divided by 10, becomes a perfect square. What are the four consecutive odd numbers?

#562. Find the number of terms in the Geometric series:
0.03, 0.06, 0.12, ..... 1.92.

#563.The third term of a Geometric Progression is 1 and the fifth term is 2. What is the seventh term?

#564.  Find the Greatest Common Divisor of

and
.

#565. Find the Least Common Multiple of

and
.


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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#304 2009-02-07 17:46:54

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#566. The weight of an empty vessel is 10% of the weight of the vessel when filled with a certain liquid. Some of the liquid is poured into another container. The, the vessel, along with the remaining liquid, weighs half of the initial weight. What fraction of the liquid has been poured into the other container?

#567. What is the value of

?

#568. What is the value of

?

#569. What is the value of

?

#570. If P is a Polygon with vertices on a circle of radius 1 unit, which of the following is/are true?
(I) The perimeter of P is less than

.
(II)
is greater than the area of P.
(III) The side of the polygon is greater than 1.

(1) I
(2) II
(3) III
(4) I and II only
(5) I, II, and III.


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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#305 2009-02-07 18:26:14

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#571. If 4, x, 0.04 are in Geometric Progression, what is the value of x?

#572. The sum of two numbers is 97 and their difference is 37. What is their product?

#573. What is the value of

?

#574. What is the perimeter of a square whose area is equal to that of a circle of circumference

?

#575. The sum of a two digit number and the number obtained by interchanging the digits is 88. What is the sum of the two digits of the number?


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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#306 2009-02-10 03:22:22

Jai Ganesh
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Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#576. When 50% of a number is added to a second number, the second number increases to its four-third. What is the ratio of the first number to the second number?

#577. A right circular cone is exactly fitted inside a cube in such a way that the edges of the base of the cone touch the edges of one of the faces of the cube and the vertex is on the opposite face of the cube. If the volume of the cube is 343 cubic centimeters, what is the volume of the cone approximately?


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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#307 2009-02-12 02:45:56

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#578. The perimeter of a square and the circumference of a circle are equal. Whose area is larger?

#579. Which is the greatest number that would leave the same remainder when 55, 125, and 175 are divided by the number?

#580. What is the value of

?

#581. What is the value of

?

#582. If x + y + z = 0, what is the value of (x+y)(y+z)(x+z)?

#583. What is the remainder when

is divided by
?

#584. What is the value of

?

#585. What is the value of

?

#586. What is the value of

?

#587. What is the value of k if the equation

has equal roots?


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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#308 2009-02-13 04:02:51

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#588. What is the value of x such that

?


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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#309 2009-02-15 00:20:33

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#589. What is the value of

?


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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#310 2009-02-15 08:29:58

emadstats
Member
Registered: 2009-02-13
Posts: 9

Re: Oral puzzles

the answer to the 12 is 22.5 degrees

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#311 2009-02-15 08:31:13

emadstats
Member
Registered: 2009-02-13
Posts: 9

Re: Oral puzzles

the answer to 12 is 22.5 degrees

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#312 2009-02-15 17:45:29

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

Answer to #12 is correct, emadstats!
xln104.jpg


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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#313 2009-02-16 03:29:22

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#590. The salary of X increases every year by 10% in the month of April. If his salary in June, 1999 was $12,000, what was his salary in September, 2001?

#591. A boat covers a distance of 12 kilometers in 2 hours while moving downstream. It covers the same distance in 3 hours while moving in still waters. What is the speed of the current in kilometers per hour?

#592. Rahim sold a cupboard for $6,000 and earned a profit of 25%. What was the Cost Price of the cupboard?

Find the wrong number in the given series:

#593. 6, 12, 36, 144, 722, 4320, 30240

#594. 4, 5, 9, 20, 34, 59, 95

#595. 2, 13, 76, 377, 1506, 4507, 9008


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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#314 2009-02-20 02:33:48

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#596. The contents of two vessels containing water and milk in the ratio 1:2 and 2:5 are mixed in the ratio 1:4. What  is the ratio of water to milk in the resulting mixture?

#597. In a mixture of 60 liters, the ratio of milk and water is 2:1. What amount of water must be added to make the ratio 1:2?

#598. A 70 liter mixture of water and milk contains milk and water in the ratio 2:3. If 14 liters of milk is added to it, what would be the ratio of milk and water in the resultant solution?

#599. A mixtyre contains milk and water in the ratio 5:1. On adding 5 liters of water to it, the ratio of milk to water becomes 5:2. What is the quantity of milk in the mixture?

#600. Two containers of equal volume contain milk and water in the ratio 3:5 and 5:3 respectively. If the contents of both the containers are emptied inot a third one, what would be the ratio of milk and water in that container?


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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#315 2009-02-20 02:57:19

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#601. The difference between the circumference of a circle and its radius is 37 centimeters. What is its circumference?

#602. A picture 30 x 20 centimeters has a frame 2½ centimeters wide. The area of the picure is approximately how many times the area of the frame?

#603. Find the ratio of the areas of the incircle and circumcircle of a square.

#604. Four horses are tethered at four corners of a square plot of side 63 meters such that they cannot reach one another. What is the area left ungrazed?

#605. A wire can be bent in the form of a circle of radius 56 centimeters. If it is bent in the form of a square, what would the area be?


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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#316 2009-02-23 03:48:13

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#606. What are the values of x and y if

?

#607. If the Arithmetic Mean and Harmonic Mean of two numbers are 9 and 4, what is their Geometric Mean?

#608. What are the two values of x which satisfy the equation

?

#609. The arithmetic mean of three observations is x. If the values of the first two observations are y and z, what is the value of the third observation?

#610. If two polynomials of degree 7 and 3 respectively are multiplied, what is the maximum possible value of the degree of the resulting polynomial?

#611. What is the value of

?

#612. Let A and B be two non-empty subsets of a set X. If

,
then which of the following is correct?
(1)

(2)

(3)

(4)


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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#317 2009-02-27 04:24:12

Jai Ganesh
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Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#613. Simplify:-

.

#614. Find the intercepts made by the straight line 3x - 2y - 6 on the x-axis and the y-axis.

#615. The center of a circle is (6, 14). A diameter of the circle has its one end at the origin. Find the other end.

#616. If sinA = cosA where A is an acute angle, find the value of 2tan²A - sin²A - 1.

#617. What is the probability that a leap year selected at random would contain 53 Sundays?


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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#318 2009-02-28 03:32:50

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#618. An urn contains 9 red, 7 white and 4 black balls. If two balls are drawn at random, find the probability of one being white and the other being red.

#619. A word consists of 9 letters; 5 consonants and 4 vowels. Three letters are chosen at random. What is the probability of more than one vowel being selected?

#620. One card is drawn from a pack of 52 cards, each of the 52 cards being equally likely to be drawn. Find the probability of the card drawn being either red or a King.

#621. If two dice are tossed simultaneously, what is the number of elements in the sample space?

#622. A bag contains 10 apples out of which 4 are rotten. two apples are to be taken out together. If one of them is found to be good, what is the probability of the other apple being good too?

#623. An article manufactured by a factory consists of two parts X and Y. In the process of manufacture of part X, 9 out of 104 parts turn out to be defective. Similarly, 5 out of 100 parts of part Y manufactured are defective. What is the proabibility of an assembly of a part X and a part Y not being defective?


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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#319 2009-02-28 18:24:17

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#624. Which of the following has the maximum area?
(1) A circle of radius 2 units.
(2) An equilateral triangle of side 4 units.
(3) A square of side 2 units.
(4) A triangle with sides 3 units, 4 units, and 5 units.

#625. A right circular cone, a right circular cylinder and a hemisphere have the same radius and the heights of the cone and the cylinder are equal to their diameters. Then, what is the ratio of their volumes?


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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#320 2009-03-01 19:15:40

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#626. When a rectangular sheet of paper is halved by folding it at the midpoints of the longer sides, the resultant shape is a rectangle whose longer sides and shorter sides are in the same proportion as the longer and shorter sides of the original rectangle. If the shorter side of the original rectangle is 2 centimeters, what is the approximate ratio of the perimeters of the smaller rectangle to that of the the original rectangle?

#627. An empty crate, with a capacity of 50 oranges costs $7.25. Each orange costs $0.75 for the first 15 fruits bought, and every extra orange costs $0.50. If a fruit-seller has $31.00 with him, what is the maximum number of oranges he can buy, if he has to also buy the required number of crates to put them in?

#628. A task was set to deliver building material from a railway station to a construction site in 8 hours. The material had to be delivered with 30 three ton trucks. These trucks were put to use for 2 hours, and then 9 five ton trucks were added to help the task finish in time.If the work was completed in exactly the time scheduled, determine how many hours it would take
(i) one three ton truck alone to deliver all the material?
(ii) one five ton truck alone to deliver all the material?

#629. If today is January 5th and four days after today is a Saturday, what day of the week was December 3rd of the previous year?


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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#321 2009-03-02 02:07:33

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#630. If

,
what are the minimum and maximum values of
?

#631. What is the value of

?


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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#322 2009-03-04 05:57:51

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

Re: Oral puzzles

Last edited by JaneFairfax (2009-03-04 07:53:13)

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#323 2009-03-04 16:26:58

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

Answer to #631:-
Correct, JaneFairfax!
Outstanding5.gif


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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#324 2009-03-05 17:34:06

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#632. If a = 1000, and b = 100, what is the value of

?

#633. What is the Least Common Multiple of

and
?

#634. What is the remainder when f(x) is divided by ax+b?

#635. If p and q are the roots of the equation

, then what is the value of
?

#636. A solid sphere of radius 8 cm is made into a number of smaller spheres of radius 1 cm. How many such smaller spheres can be made?

#637. If 71 is the n[sup]th[/sup] term of the sequence 13, 15, 17, ....., what is the vlue of n?

#638. How many terms are there in the series 6, 18, 54, ......., 1458?

#639. What is the Greatest Common Divisor of the polynomials

?

#640.Find the sum : 15 + 16 + 17 + 18 + .....80.


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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#325 2009-03-06 20:41:12

Jai Ganesh
Administrator
Registered: 2005-06-28
Posts: 45,956

Re: Oral puzzles

#641. Which is the largest number which is a factor o all the numbers in the sequence

?

#642. The average of 7 numbers is 25. The average of the first three is 20 while that of the last three is 28. What is the value of the remaining number?


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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