Section: Mathematics Knowledge

19) √303,405 is between

1. 200 and 300
2. 300 and 400
3. 400 and 500
4. 500 and 600

Answer is (D). You only have to approximate to identify this number. You know that the square of 100 = 10,000. Therefore, calculate the squares of the hundredth number and multiply by 10,000 to get the rough numbers. I.e. the square of 200 = 2 X 2 X 10,000 = 40,000.

From this you can tell that 5 X 5 X 10,000 = 250,000 and 6 X 6 X 10,000 = 360,000. Therefore the answer is D.