I am trying to create a quiz over dividing fractions. I want it to be graded and can not figure out how to add the answers in the form of a fraction. It will not let me submit them.
Stop trying. It's not going to work. Numeric and formula questions only allow for decimal answers. Any other form of a number, including fractions and radicals, is unsupported.
With fractions, you have an opportunity that is not there with many other problems. There is a concept of a standard reduced form. You could tell your students to enter the results in the form that you want and then use a fill-in-the-blank question. In the instructions, you would need to be specific about lowest form, do not enter any spaces, enter numbers as improper fractions not mixed numbers, and anything else. Fill in the blank questions are specific and the answers need to match exactly. They do not understand math, it does a simple string comparison of what the student enters to what you enter as the answer. Fill in the blank questions also prevent you from generating lots of questions easily like you can with formula questions, so you would need to manually create questions and put them into a question group if you want variations.
Another option would be to go to the micro-level and ask for the numerator or the denominator before reducing fractions. That would allow you to have a formula question so you could get many versions. Because you're asking for one or the other, it doesn't need the fraction bar so it will take it as an answer.
Example: What is the numerator, before performing any possible reducing, in [a] / [b] divided by [c] / [d] ?
Many people find that you either don't ask math questions with Canvas or you find creative ways to ask them. If you don't ask them in Canvas, you find a third party solution that does homework and/or assessment and use it.
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