Idon’t know how you do 17.1 divided by 0.9.

The answer is 19

work :

1-multiply the numbers by a submultiple of 10 to remove the decimal points.


2-

now do the division :


so the answer is 19

note: there is no need to get it back to decimal number unless you multiply just one of the numbers or multiply the numbers with different submultiples of 10

good luck

First you can multiply both numbers by 10 to remove the decimals

Then you just divide 171 by 9
=19