The easiest way to order these numbers from least to greatest is to solve the fractions and convert them into a decimal number
[tex]\frac{4}{5}=0.8[/tex][tex]\frac{7}{10}=0.7[/tex]Now, you can order these numbers this way:
0.1
0.7
0.8
It means, the correct order (from least to greatest) is: 0.1, 7/10, 4/5.