4523 is a four digit number. In this number where can be 0 placed so that it doesn't change the value of this number?

Answer: A. At the place of ten thousand

The answer is A. At the place of ten thousand.
In a whole number, placing a 0 to the left of the existing digits (the leading position) does not change its value. In the number 4523, the highest place value is the thousand place (4). The next place to its left is the ten thousand place.
Writing the number as 04523 is exactly the same as 4523.

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