Moving the decimal over one space to the left. (9.852)
Explanation: If you multiply a decimal by 10 the decimal point will move one space to the right to make a bigger number. But, if you divide by 10, it will move one space to the left to make a smaller number. (÷ means left, x means right) The The rule is, however many 0’s you have after the 1, that is how many spaces you move your decimal point. For an example if I wanted to multiply or divide a decimal by 100, I would move the decimal point 2 spaces over instead of just one because the number 100 had two 0’s after the one.This rule will not work with numbers like 20, or 150, because they are not multiples of 10 like the other numbers. Numbers that will work are 10, 100, 1000, 10000, 100000 and so on.
Sorry this is so long, I just wanted to make sure you understand because I had trouble with it when I was learning it.