The question is poorly formatted, so I'll try to figure out what conversions you want.
If you have the fraction, just perform the division and look for the result:
[tex]\dfrac{3}{10}=0.3[/tex]
[tex]\dfrac{6}{8}=0.75[/tex]
If you have numbers, build a fraction as follows:
0.9 is 9/10
0.4 is 4/10
1.4 is 14/10