Write 3/5, 1 2/3, 15/7, 1/2, 2 5/8, and 9/4 in order from least to !

3/5, 1 2/3, 15/7, 1/2, 2 5/8, 9/4

Fractions less than one: 3/5, 1/2
Fractions between one and two: 1 2/3
Fractions more than two: 15/7, 2 5/8, 9/4
^ this gives you a general order of the fractions ^

Fractions less than one (least to greatest):
3/5 * 2 = 6/10
1/2 * 5 = 5/10
Order - 1/2, 3/5

Fractions between one and two (least to greatest): 
1 2/3

Fractions more than two (least to greatest):
15/7 * 8 = 120/56
2 5/8 = 21/8 --> 21/8 * 7 = 147/56
9/4 * 14 = 126/56
Order - 15/7, 9/4, 2 5/8

Now put the orders together to get your final answer...
1/2, 3/5, 1 2/3, 15/7, 9/4, 2 5/8