Could you just tell me what am I doing wrong? I've tried hundreds of times..

In C2 I have the following function:
=IF((B2<="0,15");"10";IF(("0,15"<B2<="0,4");"20";IF(("0,4"<B2<="0,58");"30";IF(("0,58"<B2<="0,8");"40";IF(("0,8"<B2<="0,93");"50";"")))))

The number that i've got in B2 is 0,534577706840502 but the computer insists that C2=10


Thank you so much