Can Seven Integers with a Subtraction of 3 Result in a Product 13 Times Larger?

In summary, the conversation discusses taking seven positive integers and subtracting 3 from each of them, and whether the resulting product can be 13 times the product of the original numbers. The participants agree that this is possible and discuss the potential number of solutions.
  • #1
Evgeny.Makarov
Gold Member
MHB
2,436
4
Take seven positive integers and subtract 3 from each of them. Can the product of the resulting numbers be exactly 13 times the product of the original numbers?
 
Mathematics news on Phys.org
  • #2
Evgeny.Makarov said:
Take seven positive integers and subtract 3 from each of them. Can the product of the resulting numbers be exactly 13 times the product of the original numbers?
Point of confusion:
If you take value away from a given set of numbers then the product of the first set will be larger than the second set automatically. The only way out of it is to have a "1" in the original set, which would put a "-2" in the second set, doubling the absolute value. That doesn't sound to me like it is a feature you wanted in the problem. Am I missing something?

-Dan
 
  • #3
Dan, your understanding is correct. And since the situation you are describing is inevitable, it should be considered.
 
  • #4
My solution

none of the numbers in 1st set can be 3 then 2nd product is zero and all cannot be >3 as product becomes smaller.
some of the numbers have to be 1 or 2. and number of numbers 1 or 2 has to be even or product is -ve.
as product of second set of numbers is multiple of 13 so one of the numbers shall be 13 or a multiple of the same.
so we have one number in 1st set 16 and corresponding number in 2nd set 13.
we need one or more numbers so as to mulitply 2nd set by 16 and pair of (1,-2) gives multiplication by -2 so if we take 4
times product by 16 is compensated
so 1st set (16,1,1,1,1,x,y) and 2nd set(13,-2,-2,-2,-2,x-3,y-3). we need to choose x,y such that xy = (x-3)(y-3) and x= 1, y = 2
gives x-3 = -2 and y-3 = -1 so the criteria is met
so numbers = (16,1,1,1,1,1,2)

Hence ans is Yes
 
  • #5
Nice job. I know of one more solution, but I am not sure of how many there are.
 
  • #6
Evgeny.Makarov said:
Nice job. I know of one more solution, but I am not sure of how many there are.

I could not find the 2nd solution. I would like to know it.
 
  • #7
\(\displaystyle 1^4\cdot29\cdot61\cdot64\mapsto(-2)^4\cdot26\cdot58\cdot61\).
 

1. What is a product of seven integers?

A product of seven integers is the result of multiplying seven whole numbers together. For example, the product of 2, 3, 4, 5, 6, 7, and 8 would be 40,320 (2 x 3 x 4 x 5 x 6 x 7 x 8 = 40,320).

2. How do you find the product of seven integers?

To find the product of seven integers, you simply multiply all seven numbers together. This can be done using a calculator or by hand using the multiplication method.

3. What is the significance of the product of seven integers?

The product of seven integers is often used in mathematical equations and formulas. It can also represent the total number of unique combinations or possibilities when using seven different factors or variables.

4. Can the product of seven integers be negative?

Yes, the product of seven integers can be negative if the seven numbers being multiplied together include both positive and negative integers. The negative sign will depend on the number of negative integers and their placement in the equation.

5. What are some real-life applications of the product of seven integers?

The product of seven integers can be used in various fields such as computer science, engineering, and statistics. It can also be used to calculate the total number of outcomes in a game of chance or to determine the number of possible combinations in a lock or code.

Similar threads

Replies
4
Views
232
Replies
1
Views
654
Replies
3
Views
280
Replies
5
Views
2K
Replies
1
Views
1K
Replies
2
Views
1K
Replies
8
Views
1K
Replies
66
Views
4K
Replies
3
Views
1K
Back
Top