Note: if you have Excel 2016, simply use the IFS function.
1a. If cell A1 equals 1, the formula returns Bad.
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1b. If cell A1 equals 2, the formula returns Good.
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1c. If cell A1 equals 3, the formula returns Excellent.
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1d. If cell A1 equals another value, the formula returns No Valid Score.
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Here's another example.
2a. If cell A1 is less or equal to 10, the formula returns 350.
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2b. If cell A1 is greater than 10 and less or equal to 20, the formula returns 700.
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2c. If cell A1 is greater than 20 and less or equal to 30, the formula returns 1400.
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2d. If cell A1 is greater than 30, the formula returns 2000.
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Note: to slightly change the boundaries, you might want to use "<" instead of "<=" in your own formula..