To multiply 52.03 by 9.81, you can first ignore the decimal points and multiply 5203 by 981:
5203 x 981 = 5100843
Next, count the total number of decimal places in the original numbers being multiplied (2 in 52.03 and 2 in 9.81) and add them together to get 4.
Finally, place the decimal point in the product so that there are 4 digits to the right of the decimal point. Counting from the right, this means placing the decimal point after the third digit:
5203 x 981 = 5100843
52.03 x 9.81 = 510.0843
Therefore, 52.03 multiplied by 9.81 is equal to 510.0843.