3/5 2/5 3/7 4/9 least to greatest

2/5, 3/7, 4/9, 3/5

Step-by-step explanation:

One way of approaching this problem is to convert all four fractions to their approximate decimal forms:

0.600, 0.400, 0.429, 0.444

It's immediately obvious that 0.400 is the least of them and 0.600 the greatest. In order by least to greatest, we get:

0.400, 0.429, 0.444, 0.600, or, returning to the original formats,

2/5, 3/7, 4/9, 3/5