top button
Flag Notify
    Connect to us
      Site Registration

Site Registration

What would be the sum of all positive integers n such that 20n and 5n+275 both are perfect squares?

0 votes
385 views
What would be the sum of all positive integers n such that 20n and 5n+275 both are perfect squares?
posted May 21, 2018 by Samardeep Acharya

Share this puzzle
Facebook Share Button Twitter Share Button LinkedIn Share Button

1 Answer

0 votes

It happens only at n=125
20x125 = 2500 (50x50)
5x125 + 275 = 900 (30x30)
So sum of all such positive numbers = 125 ( its the only one).

answer May 21, 2018 by Tejas Naik



Similar Puzzles
0 votes

First 17 positive integers (1..17) are rearranged into a sequence such that the sum of any two adjacent terms is a perfect square.
What is the sum of the first and last terms of this sequence?

0 votes

If 1^3 + 2^3 + 3^3 = m^2 where m is also an integer.
What are the next three consecutive positive integers such that the sum of their individual cubes is equal to a perfect square?

...