Answer:
30
Step-by-step explanation:
Square root of a number k will turn it into a number n such that n * n = k.
The square root of 100 is 10 because 10 * 10 = 100, and the square root of 400 because 20 * 20 = 400.
Now, we just need to sum 10 and 20: 10 + 20 = 30.
Thus, the answer is 30.
Hope this helps!
