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## #5651 2017-12-20 14:00:38

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

The solution #3865 is correct. Neat work, Monox D. I-Fly!

#3866. If diameter of a circle is increased by 40%, then by what percent does its area increase?

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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## #5652 2017-12-22 01:09:01

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3867. If the area of a sector of a circle is 7/20 of the area of the circle, then find the sector angle.

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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## #5653 2017-12-22 12:57:52

Monox D. I-Fly
Member
Registered: 2015-12-02
Posts: 975

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## #5654 2017-12-22 14:28:12

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

The solution #3867 is correct. Excellent, Monox D. I-Fly!

#3868. If the area of a sector of a circle bounded by an arc of of length

cm is equal to
square centimeters, then find the radius of the circle.

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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## #5655 2017-12-24 00:33:21

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3869. The hour hand of a clock is 6 centimeters long. Find the area swept by it between 11.20 am and 11.55 am.

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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## #5656 2017-12-26 00:31:58

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3870. The radius of a wheel is 0.25 meter. Find the number of revolutions it will make to travel a distance of 11 kilometers.

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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## #5657 2017-12-28 00:21:00

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#If the difference between the circumference and radius of a circle is 37 centimeters, find its area.

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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## #5658 2017-12-28 12:47:58

Monox D. I-Fly
Member
Registered: 2015-12-02
Posts: 975

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## #5659 2017-12-28 13:59:26

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

(That was by oversight!)

The Solution #3871 is correct. Good work, Monox D. I-Fly!

#3872. If the area of a sector of a circle bounded by an arc of length

centimeters is equal to
square centimeters, then find its radius.

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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## #5660 2017-12-30 00:14:01

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3873. If

is taken as
, find the distance in meters covered by a wheel of diameter 35 centimeters, in one revolution.

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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## #5661 2017-12-31 08:19:59

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3874. If the perimeter of a circle is equal to that of a square, find the ratio of their areas.

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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## #5662 2018-01-02 01:01:25

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3875. If the circumference of a circle increases from

to
, then its area is
(a) halved
(b) doubled
(c) tripled

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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## #5663 2018-01-02 12:36:46

Monox D. I-Fly
Member
Registered: 2015-12-02
Posts: 975

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## #5664 2018-01-02 13:45:06

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

The solution #3875 is correct. Neat work, Monox D. I-Fly!

#3876. If the circumference and the area of a circle are numerically equal, then the diameter of the circle is
(a)

(b)

(c) 2
(d) 4

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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## #5665 2018-01-04 00:17:33

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3877. If the area of a circle is equal to the sum of the areas of two circles of diameters 10 cm and 24 cm, then find the diameter of the larger circle (in cm).

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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## #5666 2018-01-04 12:50:43

Monox D. I-Fly
Member
Registered: 2015-12-02
Posts: 975

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## #5667 2018-01-04 14:27:18

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

The solution #3877 is correct. Good work, Monox D. I-Fly!

#3878. The ratio of the outer and inner perimeters of a circular path is 23:22. If the paths is 5 meters wide, then find the diameter of the inner circle.

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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## #5668 2018-01-06 00:37:41

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3879. A copper rod of diameter 1 cm and length 8 cm is drawn into a wire of length 18 m of uniform thickness. Find the thickness of the wire.

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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## #5669 2018-01-08 00:25:11

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3880. The largest sphere is carved out of a right circular cylinder of radius 7 cm and height 14 cm. Find the volume of the sphere.

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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## #5670 2018-01-10 00:59:44

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3881. The diameter of a metallic sphere is equal to 9 cm. It is melted and drawn into a long wire of diameter 2 mm having uniform cross-section. Find the length of the wire.

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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## #5671 2018-01-11 23:15:24

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3882. Solve:
152x - 378y = -74,
-378x + 152y = -604.

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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## #5672 2018-01-13 00:10:01

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3883. Solve:

,
.

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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## #5673 2018-01-15 00:14:30

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

.

#3884. A box contains 90 discs which are numbered from 1 to 90. If one disc are drawn at random from the box, find the probability of it bearing
(i) a two digit number
(ii) a perfect square number
(iii) a number divisible by 5.

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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## #5674 2018-01-17 00:42:21

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3885. Find the probability of a number selected from the number 1 to 25 is not a prime number when each of the given numbers is equally likely to be selected.

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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## #5675 Yesterday 00:51:47

ganesh
Registered: 2005-06-28
Posts: 23,578

### Re: Oral puzzles

Hi,

#3886. Five cards - the ten, jack, queen, king, and the ace of diamonds, are well-shuffled with their face downwards. One card is then picked up at random.
(i) What is the probability of the card is the queen?
(ii) If the queen is drawn and put aside, what is the probability of the second card picked up is (a) an ace? (b) a queen?

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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