Excel IF formulas correction?

I am trying to apply different formulas based on the range a number is in. Can anyone help me correct this formula?

=If(AND(B4>0,B4 < 50000), 0, IF(AND(B4>49999.99,B4 < 100000),((B4-50000)*0.0275*2/3), IF(AND(B4>99999.99,B4<150000),(B4*.02+1850),IF(AND(B4>149999.99,B4<250000),(B4*.07/3+2850),IF(B4>249999.99),(B4*.08/3+5185)))))

In other words, if number is 0-50k, apply one formula, if 50k-100k, apply different formula, etc.

Any ideas how to make it work? Thank you!