One trick for finding whether or not a number is a perfect square is to subtract a series of odd numbers from it. If you get down to exactly zero, it is a perfect square. For example:
49 - 1 = 48
48 - 3 = 45
45 - 5 = 40
40 - 7 = 33
33 - 9 = 24
24 - 11 = 13
13 - 13 = 0
Because our series of subtractions led us to the number zero, we know that 49 is a perfect square. On top of that, this technique will also tell you what it's square root is. The square root of the number will be equal to the number of subtractions required to get down to zero. In this case, we made seven subtractions, which tells us that seven is the square root of forty-nine.
Then the number is called a "perfect square".Then the number is called a "perfect square".Then the number is called a "perfect square".Then the number is called a "perfect square".
For a number to be a perfect square, the number's square root has to be a whole number. 9 is a perfect square because its square root is a whole number, 3. If the square root of the number is a decimal, then it is not a perfect square. For example, 13 does not divide evenly so it not a perfect square.
If by 'perfect number' you mean 'perfect SQUARE', then yes. 49 is an odd number and a perfect square.
There is not a number that is a perfect square and perfect cube between 1 and 25.There is not a number that is a perfect square and perfect cube between 1 and 25.There is not a number that is a perfect square and perfect cube between 1 and 25.There is not a number that is a perfect square and perfect cube between 1 and 25.
20 is a not perfect square.
You take the square root of the number. If it is a perfect square, this will be a whole number. If it is not, it isn't a perfect square.
It is the definition of a perfect square.
Well, technically, it is the square of 11.18033989...but it is not a perfect square(a perfect square is the square of a whole number. 1,4,9,16,25,36,49,64,81,100,121,144,169,196,225,256, etc.)
It is a square number but not a perfect square number.
195 is a not perfect square.
No, 80 is a not perfect square.
No, 1,000 is a not perfect square.