Calculator automatic rounding is screwing up my calculation.

In summary, many calculators have a default setting that automatically rounds numbers to a certain number of decimal places for convenience. The process for changing this setting varies by calculator and can usually be accessed through a "mode" or "setting" button. If you prefer to enter and calculate numbers with more decimal places, you can turn off the automatic rounding feature. To test if your calculator is automatically rounding numbers, you can enter a number with several decimal places and see if the result is rounded. While automatic rounding should not significantly affect accuracy, for precise calculations it is best to manually round numbers to the desired decimal places.
  • #1
Lebombo
144
0
Hi,

When I type into my calculator 13.6/(1.000000001)
the calculator returns the answer 13.59999999

Then, when I type 13.6/(1.0000000001)
the calculator returns the answer 13.6.

Obviously, both 13.6/(1.0000000001) and 13.6/1 cannot equal 13.6,

so what's the deal with the calculator returning the wrong answer?
 
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  • #2
The calculator has a finite precision for displaying digits, it rounds 13.6/(1.0000000001) = 13.59999999864 (approximately) to 13.6. Try subtracting 13.6 from the result, often calculators have internally one or two more digits than they show.
 
  • Like
Likes Lebombo
  • #3
Thank you
 

FAQ: Calculator automatic rounding is screwing up my calculation.

1. Why does my calculator automatically round numbers?

Many calculators have a default setting that automatically rounds numbers to a certain number of decimal places. This is often done to make calculations easier and faster for the user.

2. How can I change the automatic rounding on my calculator?

The process for changing the automatic rounding setting on a calculator varies depending on the make and model. Generally, you can access the settings by pressing a button or combination of buttons labeled "mode" or "setting". Refer to your calculator's manual for specific instructions.

3. What happens if I don't want my calculator to automatically round numbers?

You can turn off the automatic rounding feature on your calculator by changing the appropriate setting. This will allow you to enter and calculate numbers with as many decimal places as you need.

4. How can I tell if my calculator is automatically rounding numbers?

If you are unsure whether your calculator is rounding numbers automatically, you can test it by entering a number with several decimal places and performing a calculation. If the result is rounded, then your calculator is set to automatically round numbers.

5. Can I trust the results of my calculator if it is automatically rounding numbers?

In most cases, automatic rounding should not significantly affect the accuracy of your calculations. However, if you require precise calculations, it is best to turn off the automatic rounding feature and manually round numbers to the desired number of decimal places.

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