You can change 3.25 into 3 1/4 to make it easier, so all of them have 3 as their base and then compare the fractions
out of 1/4, 2/5 and 3/8, you can change all of them into the same base, so 40
3 1/4 would be 3 10/40
3 2/5 would be 3 16/40
3 3/8 would be 3 15/40
the order, from the least to the greatest would then be
3.25, 3 3/8 and then 3 2/5
Hope this helped