Datasheet

Two types of errors can occur in formulas. In one type, Excel can calculate
the formula, but the result is wrong. In the other type, Excel is not able to
calculate the formula. Check out both of these.
A formula can work and still produce an incorrect result. Excel does not report
an error because there is no error for it to find. Often this is the result of not
using parentheses properly in the formula. Take a look at some examples:
Formula Result
=7 + 5 * 20 + 25 / 5 112
=(7 + 5) * 20 + 25 / 5 245
=7 + 5 *( 20 + 25) / 5 52
=(7 + 5 * 20 + 25) / 5 26.4
All of these are valid formulas, but the placement of parentheses makes a dif-
ference in the outcome. You must take into account the order of mathemati-
cal operators when writing formulas. The order is:
1. Parentheses
2. Exponents
3. Multiplication and division
4. Addition and subtraction
This is a key point of formulas. It is easy to just accept a returned answer.
After all, Excel is so smart. Right? Wrong! Like all computer programs, Excel
can only do what it is told. If you tell it to calculate an incorrect but struc-
turally valid formula, it will do so. So watch your p’s and q’s! Er, rather your
parentheses and mathematical operators when building formulas.
Figure 1-18:
Populating
cells with a
formula by
using the fill
handle.
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Part I: Putting the Fun in Functions
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