Answer:
[least] 1/4, 2/5 , 1/2, 3/5 [greatest]
Explanation:
Well lets find out LCD (least common denominator) for 4,5 and 2
LCD-20
12/20 =used to be 3/5
5/20=used to be 1/4
10/20=used to be 1/2
8/20=used to be 2/5
Now that you know all of them and have common denominator lets order!!
[least] 1/4, 2/5 , 1/2, 3/5 [greatest]
Hope this helps :3