You need not the use the if statement at all
Do the following
Type the range of values in text format in one column and the
corresponding values in the next column(e.g)
A B
10-20 5
20-30 6
30- 40 7
Then go to your worksheet
Type your range in cell A1(eg)10-20 in text format
in cell A2,enter the following
formula,VLOOKUP(A1,sheet1!A1:B19,2,FALSE).
Change the cell ranges to fit your need and use excel help to know
about VLOOKUP function
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