P and C

[s sriseshan]

find number of 5 digit numbers so that the digits are in ascending order.

 

there are 5 different prizes and 6 students. only 3 of them should share all the 5 prizes. find the total number of ways of doing so.

 

--
sss

[Divij]

70 i think

[Divij]

using php and perm, combo, i got it as 30

whats ur ans?

On Apr 16, 5:22 pm, "s sriseshan" <seshu6...@gmail.com> wrote:

[s sriseshan]

what's php?

i didn't try for the solution as yet. just found the qs and posted them.

[Divij]

pigeon hole principle.

On Apr 17, 9:33 pm, "s sriseshan" <seshu6...@gmail.com> wrote:
> what's php?
> i didn't try for the solution as yet. just found the qs and posted them.
>

> On 4/17/07, Divij <divij_urdb...@yahoo.co.in> wrote:
>
>
>
>
>
>
>
> > using php and perm, combo, i got it as 30
>
> > whats ur ans?
>
> > On Apr 16, 5:22 pm, "s sriseshan" <seshu6...@gmail.com> wrote:
> > > find number of 5 digit numbers so that the digits are in ascending
> > order.
>
> > > there are 5 different prizes and 6 students. only 3 of them should share
> > all
> > > the 5 prizes. find the total number of ways of doing so.
>
> > > --
> > > sss
>

> --
> sss- Hide quoted text -
>
> - Show quoted text -

[s sriseshan]

you seem to be a voracious reader. i heard that pigeon hole principle isn't part of IIT syllabus (its only for +2 olympiads).

i don't know how to do that.

please give the solution(s).

 

 

--
sss

[Divij]

i m not, i m very lazy to read books, except that of nuke chem,
astronomy and math.
the statement of php is very simple,.
by the way, is the ans correct?, wats ur soln?

On Apr 18, 7:15 pm, "s sriseshan" <seshu6...@gmail.com> wrote:
> you seem to be a voracious reader. i heard that pigeon hole principle isn't
> part of IIT syllabus (its only for +2 olympiads).
> i don't know how to do that.
> please give the solution(s).
>

[s sriseshan]

i've tasted only the definition of php only today. i don't know the answer. hope someone else from the group will verify your answer.

 

you mentioned astronomy... do you get teh concept of

sidereal time

and the astronomical coordinate system and transformations?

can you locate celestial objects by their coordinates?

 

if yes or atleast partly yes, please do explain to me... i fail to get teh total picture even after whilfing ;P

 

[Divij]

its done in the form of vectors
(i^ , j^ , k^) cap
are used to represent 3d positions.

i read basics of astronomy, and may read in detail after ramaiah exam.

u seem to be well in to it

regards,
Divij

On Apr 20, 1:46 pm, "s sriseshan" <seshu6...@gmail.com> wrote:
> i've tasted only the definition of php only today. i don't know the answer.
> hope someone else from the group will verify your answer.
>
> you mentioned astronomy... do you get teh concept of
> sidereal time
> and the astronomical coordinate system and transformations?
> can you locate celestial objects by their coordinates?
>
> if yes or atleast partly yes, please do explain to me... i fail to get teh
> total picture even after whilfing ;P
>

[s sriseshan]

interest as well as compuslsion has driven me to that. ofcourse, i don't know the concepts of everything that a person like me can understand.

[sriseshan (triple S)]

5 digit no. answer is 9C5.

On Apr 21, 6:11 pm, "s sriseshan" <seshu6...@gmail.com> wrote:
> interest as well as compuslsion has driven me to that. ofcourse, i
> don't know the concepts of everything that a person like me can understand.
>

[Divij]

the celestial bodies posns can be noted and predicted.
WEINS law can be used.
h=k/t,
h=wavelength
k=2.88x10^ -2
i think
t is temp.

thereare more theories, like shifts, red shift, blue shift.
if a star is approaching a galaxy, the distance dec, h inc, the colour
changes to red.
viceversa,colour changes to blue.
this is what i have to talk abt in this topic

regards,
Divij
On Apr 21, 6:16 pm, "sriseshan (triple S)" <seshu6...@gmail.com>
wrote:

> > - Show quoted text -- Hide quoted text -

[s sriseshan]

exactly.

that wien's displacement law (wavelenght inversely proportional to temperature) was actually there in our CBSE physics syllabus! in sources of energy.

 

sss

[sriseshan (triple S)]

the prizes question...

we can select 3 gifted students by 6C3.

by def of php, atleast 1 student should get atleast 2 prizes. right?
after that?

do we have to take cases that 1 student gets all prizes, 2 students
get all prizes and so on?
i await the solution

On Apr 22, 10:22 am, "s sriseshan" <seshu6...@gmail.com> wrote:
> exactly.
> that wien's displacement law (wavelenght inversely proportional to
> temperature) was actually there in our CBSE physics syllabus! in sources of
> energy.
>

[s sriseshan]

you mentioned i^, j^, k^... so where are the coordinate axes and where is the origin?

(i assume i^ etc. are used to represent components along that axis. right?)

wikipedia tells me there are 5 or 6 coordinate systems. can you brief me about them?

--
sss

[Divij]

> you mentioned i^, j^, k^... so where are the coordinate axes and where is
> the origin?

it is not fixed i think... may be it is, but had that been, there wud
have been a limit for the universe, which so far hasnt been
discovered.

> (i assume i^ etc. are used to represent components along that axis. right?)

right

> wikipedia tells me there are 5 or 6 coordinate systems. can you brief me
> about them?

i m not so sure of the coordinates

> > the prizes question...
>
> > we can select 3 gifted students by 6C3.
>
> > by def of php, atleast 1 student should get atleast 2 prizes. right?
> > after that?

i wud like to modify it a bit...
by php, atleast 2 shud get 2 prizes each, or one must get 3 prizes, or
atleast one person must get 1 prize

>
> > do we have to take cases that 1 student gets all prizes, 2 students
> > get all prizes and so on?
> > i await the solution

i think that is the way to go abt it.

> > > exactly.
> > > that wien's displacement law (wavelenght inversely proportional to
> > > temperature) was actually there in our CBSE physics syllabus! in sources
> > of
> > > energy.

i never knew...that was a shock that u gave me... ncert having some
gud concepts????

[s sriseshan]

it wasn't named ofcourse. take a look at the class 7 bk. good standard for the class.

[Divij]

v r totally out of the topic.

what tis the procedure?

On Apr 23, 3:25 pm, "s sriseshan" <seshu6...@gmail.com> wrote:
> it wasn't named ofcourse. take a look at the class 7 bk. good standard for
> the class.
>

[s sriseshan]

i don't understand what you  meant. out of topic... that yes, but procedure???

 

i stated that i awaited a logical solution with as few cases as possible for that prizes question...

i'm not satisfied with taking so many cases simply because the source of the question was EAMCET oriented... so there must be some trick to solve it fast.

 

answer to 5 digit nos in ascending order is surely 9C5

 

--
sss

[Divij]

no. of ways of selecting 3 out of 6 stds is 6c3.
no of ways of distributing 5 "DIFFERENT" prizes among 3 is 5p3.
ans: 6c3 x 5p3= 1200.
what were the options?
do u agree?
i m not so sure though.

On Apr 24, 1:28 pm, "s sriseshan" <seshu6...@gmail.com> wrote:
> i don't understand what you meant. out of topic... that yes, but
> procedure???
>
> i stated that i awaited a logical solution with as few cases as possible for
> that prizes question...
> i'm not satisfied with taking so many cases simply because the source of the
> question was EAMCET oriented... so there must be some trick to solve it
> fast.
>
> answer to 5 digit nos in ascending order is surely 9C5
>

[sriseshan (triple S)]

but the question says that all the 5 prizes are shared by 3 students,
which need not mean that all the 3 get prizes. the same guy could get
all five. i may be wrong in understanding the question, but however,

5p3 means you are selecting and arranging 3 prizes out of 5, i.e.,
the 3 students get only one prize each.
what happened to the other two?

it all started with php where i mentioned that atleast one student
will get atleast 2 prizes.
(you modified that into atleast 2 students; atleast 2 prizes or
something like that...)

see, for the min. condition, let the first 3 prizes go to the 3
students, one-one. so the remaining two (where are they if you take
5p3) may go to one or two students.
in any case, atleast one student will get atleast 2 prizes. (i'm sure
this isn't wrong. as i know only definition of php and haven't done
any problems based on it, i know not how to apply that into that)

i lost the question... forget about getting the calc.. the method,
approach are more important

> > - Show quoted text -- Hide quoted text -

[Divij]

5p3 means the no. of ways of distributing 5 different prizes among 3
students, a student may/maynot get a prize.
it is relative to the kind of prizes, as it also considers
arrangements.
agreed?
regards,
Divij

On Apr 25, 1:57 pm, "sriseshan (triple S)" <seshu6...@gmail.com>
wrote:

[s sriseshan]

5p3 means 5 x 4 x 3; i.e;

         first student may get any one out of 5, second may get any out of 4 (since first has taken one prize)                   and third any out of 3. it then only becomes 5p3. each student gets a maximum of 1 prize.

  or,

5p3 means out of the 5 prizes, you are selecting and arranging only 3 prizes; which you may distribute in any fashion to the students. (so where are the other two prizes?)

 

my view of the situation:

suppose first gets n prizes (n /= 1, n <= 5), second person gets m prizes and third person gets o prizes such that m + o = 5 - n.

 

(agreed?) :Q

[Divij]

strictly speaking, "the no. of ways of distributing 5 prizes among 3
ppl is 5p3"
i m not so sure ...

On Apr 26, 1:09 pm, "s sriseshan" <seshu6...@gmail.com> wrote:
> 5p3 means 5 x 4 x 3; i.e;
> first student may get any one out of 5, second may get any out of 4
> (since first has taken one prize) and third any out of 3.
> it then only becomes 5p3. each student gets a maximum of 1 prize.
> or,
> 5p3 means out of the 5 prizes, you are selecting and arranging only 3
> prizes; which you may distribute in any fashion to the students. (so where
> are the other two prizes?)
>
> my view of the situation:
> suppose first gets n prizes (n /= 1, n <= 5), second person gets m prizes
> and third person gets o prizes such that m + o = 5 - n.
>
> (agreed?) :Q
>

[s sriseshan]

is this supposed to be a group discussion or a sss-div private chat???

joining open discussions is not interfering.

if you've read what has gone on in this discussion, you'll be clear what our doubts are...

 

div, (or anyone), can you explain how you say that so strictly? here each student doesn't get one and only one prize as i'd mentioned before. i'd prefer the explaination that justifies 5p3 = 5 x 4 x 3... (here)

 

--
sss

[Divij]

by definition of permutations, the no. of ways of arranging n objects
taking r at a time is npr.
there is a meaning behind it, but its too long to be typed, as its in
mathematical language.

if one has that much patience to type, plz type it for us.
sss is correct, we want all the grp members to "interfere" plz give
your comments....

we want replies from various members, putting forward their
views...that is what is the main objective of the groups.

but sss, i think, ppl are quite busy, as ramaiah egg-jam is
approaching us. that mite be a reason.
i m sorry sid, if i bymistake discouraged you to put forward ur views,
i told u there was nothing personal, never mind.
all are reinvited to post their messages...

[Divij]

i think i wrote a bit 2 much, i meant the context only for this
article, as there are other ppl like iitasp, sid, sss n me, who are
active.

i act over exaggerated the fact that ppl have not replied.
but some more members need to take interest.

regards,
Divij

[s sriseshan]

lectures apart, does any one have a clear solution? you've got to convince... alright?

[Divij]

why is there a sudden stop of discussions?

ther has been strictly no activity since the last few days.

post gud questions if you have, it wud be appreciated.

Regards,
Divij

On Apr 29, 9:00 am, "s sriseshan" <seshu6...@gmail.com> wrote:
> lectures apart, does any one have a clear solution? you've got to
> convince... alright?
>

[s sriseshan]

people taking the group for granted...

i understand that the curfew is due to ramaiah...

just two or three public protests wont do...

 

--
sss