Download Mathematical to Excel

Microsoft Excel Basics
Lesson 09
Mathematical Operators
(More Complicated Formula)
Mathematical Operators & Hierarchy - 2
( ) Parenthesis pairs
^ Exponentiation
* Multiply and / Divide
+ Addition and – Subtraction
Z-Statistic Calculation - 3
Square Root - 7
Standard Error Calculation - 7
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Excel Basics 09 - 1
Mathematical Operators
Creating formula to handle calculations is necessary to create effective
business worksheets. Formula can take on many forms: Mathematical,
Statistical, Logical, Financial, etc. Excel has many built in functions to
handle many situations; however, the ability to build a formula with the
proper syntax is important.
The key mathematical operators are
( ) Parenthesis pairs
^ Exponentiation
* Multiply and / Divide
+ Addition and - Subtraction
Excel caries out mathematical calculations in the hierarchy shown
above. A calculator is necessary when checking mathematical formula
converted to Excel.
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Excel Basics 09 - 2
Converting … Mathematical to Excel
One of the first things we need to know is how to convert mathematical
formula to an Excel formula. You will recognize this Z-Statistic formula.
Mathematical formula
X - M
Z =
S
Excel formula are quite different since all of the equations have to be
typed on one line. We have two options for the above formula:
Excel Option 1:
Excel Option 2:
Z = X - M/S
Z = (X - M) / S
Which one do you think is correct. Let’s look at some calculations.
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Excel Basics 09 - 3
Converting … Mathematical to Excel
Because correct formula are critical, care should be taken every time
you create one in Excel. The Golden Rule is to test the formula with
some simple numbers to ensure your Excel formulation is correct. Let’s
calculate Z when X=5, M=1 and S=2. First,
Mathematically
X - M 5 - 1 4
Z=

 2
S
2
2
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Excel Basics 09 - 4
Converting … Mathematical to Excel
Let’s calculate Z when X=5, M=1 and S=2. First,
Excel Option 1:
Excel Option 2:
Z = X - M/S
Z = (X - M) / S
= 5 - 1/ 2
= (5 - 1) / 2
= 5 - .5
= (4) / 2
= 4.5
= 2
The Excel calculation hierarchy is why Option 2 is correct!
( ) Parenthesis pairs
^ Exponentiation
* Multiply and / Divide
+ Addition and - Subtraction
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Excel Basics 09 - 5
Create this formula and save it as
F02-Calculate Z Statistic
Note: The Formula Toolbar for cell A2
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Excel Basics 09 - 6
Converting … Mathematical to Excel
Let’s look at a little more complicated formula using the Excel square
root function. The formula calculates the Standard Error for large
samples from two populations.
Mathematical formula
2
1
Excel formula
2
2
S S
S=

n1 n 2
S = SQRT(S1 ^2 / n1  S2 ^2 / n 2 )
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Converting … Mathematical to Excel
Applying the Golden Rule (test the formula with some simple numbers),
let’s calculate S when S1=3, N1=30, S2=5, and N2=50.
Mathematically
2
1
2
2
2
2
3 5
S S
9 25
S=





n1 n 2
30 50
30 50
= .3+.5  .8 .89442719
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Excel Basics 09 - 8
Converting … Mathematical to Excel
Let’s calculate S when S1=3, N1=30, S2=5, and N2=50.
Excel
S = SQRT(S1 ^2 / n1  S2 ^2 / n 2 )
= SQRT(3^2 / 30 + 5^2 / 50)
= SQRT(9 / 30 + 25 / 50)
= SQRT(.3+.5)
= SQRT(.8)
=.89442719
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Excel Basics 09 - 9
Create this formula, set the decimal place
accuracy for cell A2 to 4 and and save it as
F03-Calculate Standard Error 2 Populations
Note: The Formula Toolbar for cell A2
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Excel Basics 09 - 10