Answer: The square root of 400 is 20.
Explanation:
The square root of a number is the value that, when multiplied by itself, gives the original number. To find the square root of 400, you can use the long division method or an electronic calculator.
Alternatively, you can approximate the square root of 400 by finding the nearest perfect square (a number whose square root is a whole number). In this case, the perfect squares closest to 400 are 361 and 441. Since the square root of 361 is 19 and the square root of 441 is 21, you can estimate that the square root of 400 is between 19 and 21. Since 20 is halfway between 19 and 21, you can approximate the square root of 400 to be 20.