You don't know the right answer? Pick a salary, manually calculate the desired result, then see which formula gives you that number. For example:
<tbody>
[TD="align: center"]1[/TD]
[TD="align: right"]10000[/TD]
[TD="align: center"]2[/TD]
[TD="align: right"][/TD]
[TD="align: right"]5225[/TD]
[TD="align: right"]5175[/TD]
[TD="align: center"]3[/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: center"]4[/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: center"]5[/TD]
[TD="align: right"]1250[/TD]
[TD="align: right"]76%[/TD]
[TD="align: right"]950[/TD]
[TD="align: center"]6[/TD]
[TD="align: right"]3750[/TD]
[TD="align: right"]54%[/TD]
[TD="align: right"]2025[/TD]
[TD="align: center"]7[/TD]
[TD="align: right"]5000[/TD]
[TD="align: right"]45%[/TD]
[TD="align: right"]2250[/TD]
[TD="align: center"]8[/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: right"][/TD]
[TD="align: center"]9[/TD]
[TD="align: right"]10000[/TD]
[TD="align: right"][/TD]
</tbody>
Sheet5
[TABLE="width: 85%"]
<tbody>[TR]
[TD]
Worksheet Formulas[TABLE="width: 100%"]
<tbody>[TR]
[TH]Cell[/TH]
[TH="align: left"]Formula[/TH]
[/TR]
[TR]
[TH]B2[/TH]
[TD="align: left"]=MIN(
MIN(A1,1250)*76%+MEDIAN(0,A1-1250,3750)*54%+MAX(A1-5000,0)*45%,8000)[/TD]
[/TR]
[TR]
[TH]C2[/TH]
[TD="align: left"]=IF(
A1>=5000+(5075/0.45),8000,IF(A1<=1250,A1*0.76,IF(A1<=5000,900+(A1-1250)*0.54,2925+(A1-5000)*0.45)))[/TD]
[/TR]
[TR]
[TH]C5[/TH]
[TD="align: left"]=A5*B5[/TD]
[/TR]
[TR]
[TH]C6[/TH]
[TD="align: left"]=A6*B6[/TD]
[/TR]
[TR]
[TH]C7[/TH]
[TD="align: left"]=A7*B7[/TD]
[/TR]
[TR]
[TH]A9[/TH]
[TD="align: left"]=SUM(
A5:A7)[/TD]
[/TR]
[TR]
[TH]C9[/TH]
[TD="align: left"]=SUM(
C5:C7)[/TD]
[/TR]
</tbody>[/TABLE]
[/TD]
[/TR]
</tbody>[/TABLE]