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Ron Rosenfeld Ron Rosenfeld is offline
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Default Help please... Simple calculation - with unexpected results

On Fri, 28 Jul 2006 15:24:01 -0700, MLK wrote:

I am getting unexpected results from a simple multiplication formula. Column
A contains rates, Column B contains billing discounts and Col C calculates
the billing $.

For example: Col A = 100, Col B = .44 and Column C calculation is: a2*(
50*37.5*0.85)*b2
Both Column B and C display only 2 decimals.

The answer that comes out is $70,492.79 but I'm expecting $70,125. It
appears to be calculating at 7 decimal places but should only be calculating
at 2. When I enter the actuals numbers into a function (100*1593.75*.44)
the answers comes out right (70,125).

Am I missing something basic? I have done a ton of formulas but have not
come across this before.


Excel calculates to 15 decimal places. Unless you check Precision as Displayed
under Tools/Options, the formatting will not change that.

Given:

A2: 100.004987921697
B2: 0.44228564109933

you would see 100.00 in A2, 0.44 in B2, and get the results you report in C2.

If you only want to calculate using two decimal places, you must either use
Precision as Displayed (which may have unexpected results elsewhere in your
workbook), or round the factors in A2:B2 to two decimal places.

You can either use the ROUND function within A2 and B2, or use it in C2:

=ROUND(A2,2)*(50*37.5*0.85)*ROUND(B2,2)

depending on what you want.

If you will only want two decimal precision in A2 and B2, then I would do the
rounding there.
--ron