Learn about timers on Quizzes.
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If you are creating or editing a Quiz, you will see that there is the option to make the Quiz timed.
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To make a Quiz timed, simply check the box when you are asked "Is this quiz timed?".
You will then be able to enter the amount of time that you want the Quiz to be (as in the image above).
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We now report in the reporting section exactly how long each user took on the Quiz.
However, please note that this feature was only introduced recently (13th September 2019), and so will only apply to Quizzes completed after this date.