Answer :
The answer is 1 1/2 or 1 5/10
Here is my work if you don't understand, ASK!!
Here is my work if you don't understand, ASK!!
[tex]3\frac{2}{5}=3\frac{2\cdot2}{5\cdot2}=3\frac{4}{10}=3.4\\\\1\frac{9}{10}=1.9\\\\3\frac{2}{5}-1\frac{9}{10}=3.4-1.9=\boxed{1.5}[/tex]