ok so i have something that looks like this
83,000 equal
8.3*10^4
how would i know where to place the decimal??
Standard form is of the form $\displaystyle a \times 10^n$ where $\displaystyle -10 < a < 10$ and n is an integer. To do this you find a first and then n will be the number of decimal places to the left or right you have to go to reach the original number.
With 83,000 you get 8.3 as only that is between -10 and 10. To get 83,000 from 8.3 you'd move the decimal place 4 places right so you get n=4
If you have 0.957 then you'd get a =9.57 and n=-1 because the decimal moves one place to the left
To learn how to convert between decimal (regular) numbers and "scientific notation", try some online lessons!