document.write( "Question 74653: This is a question from my son's homework.\r
\n" ); document.write( "\n" ); document.write( "\"If you have 4 horses and 4 stalls, how many different combinations can you stall the horses?\"\r
\n" ); document.write( "\n" ); document.write( "We have tried
\n" ); document.write( "1 horse stalled 4 ways. 4 horses x 4 ways is 16. But then I realize that more than one horse can be stalled togeather. So now I have confused myself so much I can't help my son.
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Algebra.Com's Answer #53627 by venugopalramana(3286)\"\" \"About 
You can put this solution on YOUR website!
This is a question from my son's homework.
\n" ); document.write( "\"If you have 4 horses and 4 stalls, how many different combinations can you stall the horses?\"
\n" ); document.write( "We have tried
\n" ); document.write( "1 horse stalled 4 ways. 4 horses x 4 ways is 16. But then I realize that more than one horse can be stalled togeather. So now I have confused myself so much I can't help my son.
\n" ); document.write( "YOUR ANSWER HOLDS FOR YOUR INITIAL BASIS OF 1 HORSE/1 HOUSE
\n" ); document.write( "WELL YOUR DOUBT IS GENUINE.
\n" ); document.write( "BUT THAT SHOULD BE A PART OF QUESTION.
\n" ); document.write( "WHETHER 1 STALL CAN HOUSE ONLY 1 HORSE OR MORE.
\n" ); document.write( "ASSUMING WE CAN PUT 0 TO 4 HORSES IN 1 , THE ANSWER IS AS FOLLOWS
\n" ); document.write( "IF WE DENOTE X1,X2,X3,X4 ARE THE NUMBER OF HORSES IN THE 4 HOUSES,
\n" ); document.write( "THEN THE PROBLEM IS EQUIVALENT TO FINDING NUMBER OF INTEGRAL
\n" ); document.write( "SOLUTIONS FOR THE EQUATION
\n" ); document.write( "X1+X2+X3++X4=4 WITH THE CONDITION THAT
\n" ); document.write( "X1>=0,X2>=0,X3>=0 AND X4>=0
\n" ); document.write( "THIS CAN BE TAKEN AS FINDING THE COEFFICIENT OF X^4 IN THE EXPANSION
\n" ); document.write( "(X^0+X^1+X^2+X^3.......)^4 [HERE X^0 SIGNIFIES PUTTING 0 HORSES
\n" ); document.write( "IN 1 HOUSE,X^1 MEANS PUTTING 1 HORSE IN 1 HOUSE ETC..POWER OF 4 FOR
\n" ); document.write( "THE WHOLE SUM SIGNIFIES 4 HOUSES AS ALL THE 4 HOUSES HAVE SAME
\n" ); document.write( "POSSIBILITY.
\n" ); document.write( "THOUGH WE DONT NEED TO PUT BEYOND X^4,THERE IS NO HARM IN PUTTING
\n" ); document.write( "THOSE TERMS,AS WE ARE FINALLY TAKING COEFFICIENT OF X^4 ONLY,
\n" ); document.write( "AND THERE IS AN ADVANTAGE TO BE HAD AS YOU CAN SEE BELOW
\n" ); document.write( "WE KNOW THAT
\n" ); document.write( "1/(1-X)=1+X+X^2+X^3+.......
\n" ); document.write( "SO WE HAVE TO FIND COEFFICIENT X^4 IN 1/(1-X)OR IN (1-X)^(-4)
\n" ); document.write( "= USING BINOMIAL FORMULA....
\n" ); document.write( "=[(-1)^4][(-4)(-5)(-6)(-7)/4!
\n" ); document.write( "=840/24=35
\n" ); document.write( "
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