The number of positive integral solutions is to be found

In summary, the conversation discusses finding the number of positive integral solutions for the equation xyz=3000. The equation is factored into primes and a combinatorics question is presented. Different methods are considered, including using AM>GM and the multinomial theorem. Ultimately, it is determined that the answer is 9P7/(3!)^2.
  • #1
ack
7
0
I am preparing for an entrance and I came across this sum.The equation given is xyz=3000. we need to find how many positive integral solutions are there for x,y and z.
Please help.
 
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  • #2
Let's factor 3000 into primes.
We are left with 23*3*53.

Now we are left with a very simple combinatorics question. Can you figure it out? Think about what items you are selecting and what you are placing them into.
 
  • #3
I already tried that.x can be 2^0,2^1,2^2or2^3 that is 4 ways ,2ways for 3and 4ways for 5.But what about y?
I thought of another method ,
using AM>GM,

x+y+z>=43 and max can be 3002 (when one of them is 3000 nd the other two 1 each.)
Then use multinomial theorem.Can this be done?
 
  • #4
ack said:
I already tried that.x can be 2^0,2^1,2^2or2^3 that is 4 ways ,2ways for 3and 4ways for 5.But what about y?
I thought of another method ,
using AM>GM,

x+y+z>=43 and max can be 3002 (when one of them is 3000 nd the other two 1 each.)
Then use multinomial theorem.Can this be done?
You are vastly overthinking this.
Consider the following problem: we have 3 red balls, 3 blue balls, and a green ball. How many different ways can we allocate them between 3 buckets?
 
  • #5
Oh!...then the answer would be
9P7/(3!)^2.
thanks a lot!
 
  • #6
Oh!...then the answer would be
9P7/(3!)^2.
thanks a lot!
 
  • #7
Supposing we were to find all integral solutions?
 

FAQ: The number of positive integral solutions is to be found

What does "positive integral solutions" mean?

"Positive integral solutions" refers to the set of whole numbers (also known as integers) that are greater than zero, and can be used to solve a given equation or problem.

How do you find the number of positive integral solutions?

The number of positive integral solutions can be found by using mathematical techniques such as combinatorics, algebraic manipulation, or by creating a table or chart to systematically list out all possible solutions and then counting them.

Can there be multiple solutions for the same equation?

Yes, there can be multiple positive integral solutions for a given equation. These solutions can be found by systematically substituting different values for the variables in the equation until a valid solution is found.

Are there any limitations to finding positive integral solutions?

Yes, there are limitations to finding positive integral solutions. These limitations can vary depending on the specific equation or problem being solved and may include restrictions on the values of the variables, the number of variables, or the type of equation.

How are positive integral solutions used in real-life applications?

Positive integral solutions are used in various real-life applications such as in engineering, computer science, and economics to solve problems and make predictions. For example, they can be used to find the optimal number of items to produce in a manufacturing process or to determine the most efficient route for a delivery truck.

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