Math Is Fun Forum
  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#4851 2014-05-25 04:26:21

ShivamS
Member
Registered: 2011-02-07
Posts: 3,528

Re: 10 second questions

No problem. smile

Last edited by ShivamS (2014-05-25 04:28:08)

Offline

#4852 2014-05-25 04:27:17

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: 10 second questions

Hi ganesh;

That is okay.


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Offline

#4853 2014-05-26 00:21:17

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi ShivamS and bobbym,

The solution #4990 is perfect. Marvelous!

#4991. Find the greatest number of five digits which is a perfect square.

#4992. Find the smallest number that must be added to 1780 to make it a perfect square.


Character is who you are when no one is looking.

Offline

#4854 2014-05-26 00:33:13

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: 10 second questions

Hi;


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Offline

#4855 2014-05-26 01:25:56

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi bobbym,

The solutions #4991 and #4992 are correct. Excellent!

#4993. If

, find the value of
.

#4994. If

and
, find the value of
.


Character is who you are when no one is looking.

Offline

#4856 2014-05-26 01:37:34

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: 10 second questions

Hi;


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Offline

#4857 2014-05-26 07:51:20

ShivamS
Member
Registered: 2011-02-07
Posts: 3,528

Re: 10 second questions

Are we allowed to use a calculator? The only way of solving

#4991. Find the greatest number of five digits which is a perfect square.

in 10 seconds is by taking the square root of 99999 and then squaring 316.

Offline

#4858 2014-05-26 08:04:49

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: 10 second questions

You could know that the square root of 10 is about 3.16, now you can easily get the square root of 100000


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Offline

#4859 2014-05-27 02:05:13

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi bobbym and ShivamS,

The solutions #4993 and #4994 are correct. Brilliant, bobbym!

ShivamS, the complete

#4995. Solve the following system of equations :

and

#4996. Solve the following system of equations : 11x - 7y = xy and 9x - 4y = 6xy.


Character is who you are when no one is looking.

Offline

#4860 2014-05-27 02:14:16

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: 10 second questions

Hi;


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Offline

#4861 2014-05-27 02:32:35

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi ShivamS,

Solution : #4991.
The greatest number of 5 digits is 99999.
316 x 316 + x = 99999
(knowing square root of 10 = 3.16)
Required number = (99999 - 143) = 99856.


Character is who you are when no one is looking.

Offline

#4862 2014-05-27 14:37:25

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi bobbym,

The solutions #4995 and #4996 are correct. Excellent!

#4997. Find the value of

#4998. Find the value of x.


Character is who you are when no one is looking.

Offline

#4863 2014-05-27 14:47:21

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: 10 second questions

Hi;



In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Offline

#4864 2014-05-27 16:25:05

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi bobbym,

The solution #4998 is perfect. Remarkable!

#4999. Find the value of x.

.

#5000. Find the value of x.


Character is who you are when no one is looking.

Offline

#4865 2014-05-27 22:14:30

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: 10 second questions

Hi ganesh;

Can you explain what you mean by 6.25 of x? I have been treating it as x.


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Offline

#4866 2014-05-28 00:32:36

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi bobbym,

In the problems #4999 and #5000, the operation '6.25 of x' is to be treated as

;
and
is to be treated in a similar way. However, the priority is foremost on 'of' operation, followed by division, then multiplication.


Character is who you are when no one is looking.

Offline

#4867 2014-05-28 00:48:24

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: 10 second questions

Hi;

Okay, thanks for the explanation, I will try the problems.


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Offline

#4868 2014-05-28 00:53:53

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi bobbym,

#5001. Find the value of x.

#5002. Find the value of x.

.


Character is who you are when no one is looking.

Offline

#4869 2014-05-28 01:00:46

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi bobbym,

The solutions #4999 and #5000 are perfect. Remarkable!

The only problems to be solved in '10 second questions' are #5001 and #5002.


Character is who you are when no one is looking.

Offline

#4870 2014-05-28 01:01:49

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: 10 second questions

Hi ganesh;


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Offline

#4871 2014-05-28 17:27:58

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi bobbym,

The solutions #5001 and #5002 are correct. Fantastic performance!

#5003. If

, find the value of

.

#5004. Find the difference between

and its reciprocal.


Character is who you are when no one is looking.

Offline

#4872 2014-05-28 19:39:01

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: 10 second questions

Hi;


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Offline

#4873 2014-05-29 00:30:53

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi bobbym,

The solutions #5003 and #5004 are correct. Marvelous!

#5005. When a ball bounces, it rises to

of the height from which it fell. If the ball is dropped from a height of 32 meters, how high will it rise at the third bounce?

#5006. A person travels 3.5 kilometers from place A to B. Out of this distance, he travels

kilometer on bicycle,
kilometer on motorbike and the rest on foot. What portion of the whole distance does he cover on foot?


Character is who you are when no one is looking.

Offline

#4874 2014-05-29 00:37:53

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: 10 second questions

Hi;


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Offline

#4875 2014-05-29 16:45:10

ganesh
Moderator
Registered: 2005-06-28
Posts: 14,367

Re: 10 second questions

Hi bobbym,

The solution #5005 is correct. Excellent!

The solution #5006 is also correct; The required distance on foot =

kilometer.
The required fraction =
.

#5007. Simplify :

.


Character is who you are when no one is looking.

Offline

Board footer

Powered by FluxBB