The number 320 is not a perfect square, and, therefore, its square root is a decimal number. Hence, the square root of 320 is slightly less than 18, or about 17.89. The division method is used to obtain the square root of 320.

There are two methods of finding the square root of a number. The prime factorization method is best used when the given number happens to be a perfect square. The continuous division method is a good method for all numbers.

The best way to find the square root of a number like 320 is to use the method of division and get the answer up to at least two decimal places. This method can be used to get the square root of any number. To divide 320, one must divide in pairs two numbers starting from the right. Hence, begin with one as the divisor, as 2 x 2 = 4. This yields a remainder of two. One can add as many zeros as needed in pairs after placing a decimal after 320. This yields 17.89 as the square root of 320 up to two decimal places.