Math Is Fun Forum

NullRoot

Member

Registered: 2007-11-19

Posts: 162

Re: Oral puzzles

If you have two numbers, A and B, then the percentage of B that is represented by A is: (A/B)*100

If the price of 12 pencils is x, and 1x is the profit he makes from 8x, then the percentage percentage profit is:
(1x/8x)*100

By rules of multiplication, 1x/8x = (1/8)*(x/x) = (1/8)*(1) = 1/8

So, his percentage profit is: (1/8)*100 = (0.125)*100 = 12.5%

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Trillian: Five to one against and falling. Four to one against and falling… Three to one, two, one. Probability factor of one to one. We have normality. I repeat, we have normality. Anything you still can’t cope with is therefore your own problem.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

#426.The factorial  of  a  number  is always  less  than

. True or false?

#427. If the sum of internal angles of a polygon is 720° , what is the name of the polygon?

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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.

JohnnyReinB

Member

Registered: 2007-10-08

Posts: 453

Re: Oral puzzles

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"There is not a difference between an in-law and an outlaw, except maybe that an outlaw is wanted"

Nisi Quam Primum, Nequequam

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

Correct, JohnnyReinB,
[color=ff0099]Well done![/color]

#428. If x+y=7 and xy=12, what is the value of x² +y² ?

#429. If x^(1/3)+y^(1/3)+z^(1/3)=0, then x+y+z=3xyz, True or False?

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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.

JohnnyReinB

Member

Registered: 2007-10-08

Posts: 453

Re: Oral puzzles

Have we Plutoins no hope?

Last edited by JohnnyReinB (2007-12-07 15:03:31)

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"There is not a difference between an in-law and an outlaw, except maybe that an outlaw is wanted"

Nisi Quam Primum, Nequequam

pi man

Member

Registered: 2006-07-06

Posts: 251

Re: Oral puzzles

Quote from JohnnyReinB: "What happens if you raise a number to a fraction?"

x ^ (1/2) is the square root of X
x ^ (1/3) is the cube root of X
.
.
.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

#430. What is the side total of a magic square containing numbers from 1 to 49?

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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.

TheDude

Member

Registered: 2007-10-23

Posts: 361

Re: Oral puzzles

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Wrap it in bacon

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

Well done, TheDude,
All answers correct!!!

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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.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

#431. If x=y=2z and xyz=256 then what is the value of x?

#432. Pipe A can fill in 20 minutes and Pipe B in 30 mins and Pipe C can empty the same in 40 mins.If all of them work together, find the time taken to fill the tank.

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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.

JohnnyReinB

Member

Registered: 2007-10-08

Posts: 453

Re: Oral puzzles

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"There is not a difference between an in-law and an outlaw, except maybe that an outlaw is wanted"

Nisi Quam Primum, Nequequam

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

Excellent, JohnnyReinB!!! All correct!!!

#433. Solve for x.

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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.

NullRoot

Member

Registered: 2007-11-19

Posts: 162

Re: Oral puzzles

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Trillian: Five to one against and falling. Four to one against and falling… Three to one, two, one. Probability factor of one to one. We have normality. I repeat, we have normality. Anything you still can’t cope with is therefore your own problem.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

Solution to #433.
Well done, NullRoot! You are correct!!!
#434. What is (a-x)(b-x)(c-x).......(z-x)?

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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.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

#435. Solve

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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.

JohnnyReinB

Member

Registered: 2007-10-08

Posts: 453

Re: Oral puzzles

what do you mean by solving it?

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"There is not a difference between an in-law and an outlaw, except maybe that an outlaw is wanted"

Nisi Quam Primum, Nequequam

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

Solve for x, that is get x in terms of a and b.

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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.

JohnnyReinB

Member

Registered: 2007-10-08

Posts: 453

Re: Oral puzzles

ok.

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"There is not a difference between an in-law and an outlaw, except maybe that an outlaw is wanted"

Nisi Quam Primum, Nequequam

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

No, you are not correct!

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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.

TheDude

Member

Registered: 2007-10-23

Posts: 361

Re: Oral puzzles

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Wrap it in bacon

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

Excellent, TheDude!!!
Keep it up!!!

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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.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

436. If the operation,^ is defined by the equation x ^ y = 2x + y, what is the value of a in
2 ^ a = a ^ 3?

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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.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

437. A right circular cylinder and a sphere have the same volume and same radius. What is the ratio of their curved surfaces?

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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.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Oral puzzles

438. What is the value of

?
(a) log 5
(b) -log 2
(c) 2 log 3
(d) 2 log 2

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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.

NullRoot

Member

Registered: 2007-11-19

Posts: 162

Re: Oral puzzles

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Trillian: Five to one against and falling. Four to one against and falling… Three to one, two, one. Probability factor of one to one. We have normality. I repeat, we have normality. Anything you still can’t cope with is therefore your own problem.