Question

Three and eight hundred fifty two thousandths .

Write decimals in standard form

Answer 1

3.852 I think this is the right answer

Answer 2

Let's break it down.

Obviously, three is 3.
"And" means decimal point. 
Eight hundred fifty two is obviously 852.
Thousandths is simply the number place the last number "2" is on.

So:
3.852