Forum Discussion
Using Copy/Fill Excel
I create a pattern to fill down. The pattern starts with 3.50%, in the next cell 3.75%. I select both cells and then use the copy/fill tool to copy down to 7.00%. After the fill, when I click on 6...
Excel has always behaved this way, but when exactly it occurs is hard to pin down.
In your example, enter 3.5% in F5, then enter the formula =ROUND(F5+0.25%,4) in F6, and fill down from F6.
(We round to 4 decimal places since 0.01% = 0.0001)
Sounds like something is broken. Thank you for the work around.
No, it is not broken - it is due to the way computers in general, and Excel in particular, handle fractions. We humans use decimal (10-based) numbers, while computers binary (2-based) numbers. Most decimal fractions cannot be represented exactly as binary numbers, so when converting from decimal to binary and then back from binary to decimal, tiny rounding errors occur.
- Ah! Then I guess I need to let the textbook publisher know not to use fractions when wanting students to use the fill/copy tool. I for sure will let my students know to double check; they haven't learned the ROUND function yet! Thank you.