Limits for numerical questions in Old Quizzes

[WadeGreen]

I'm editing a quiz I inherited that is in the Old Quiz format and trying to create a numerical question with a very small answer (1.34e-5) and the editor keeps defaulting my answer to zero. I get the same behavior when trying to edit the error margin box.

Is there a limit to the range of numbers Canvas will accept? I know that it can deal with the scientific notation, but it doesn't seem to like my very small numbers. I did try previewing the quiz and it did accept an answer of zero, which it should count as wrong.

Any ideas? TIA

[James · Accepted solution]

@WadeGreen 

From the Canvas Instructor Guide's lesson: How do I create a numerical answer quiz question?

If none of the possible answers are precision answers, the student answer fields round to four decimal places.

That means the smallest absolute value you can represent is 0.0001. Anything smaller than 0.00005 will be rounded to 0. This is what you're experiencing.

However, if you tell it you have an "answer with precision" instead of "exact answer" or "answer in the range", then you can get smaller numbers. It starts looking at significant digits.

If you type the answer as 1.34e-5, it changes it to 0.0000134000 because the default precision is 10. If you change the precision to 7, then you get 0.0000134.

You can go up to 16 digits of precision. If your number gets smaller than 1e-6, it displays it in scientific notation, but it allows for really small (or large) numbers. If you use a precision answer then numbers of at least 1000 get written in scientific notation.

More information about precision is available in that lesson I linked to.