Numeric answers
Ask for a number and let Praktikal check it. You set the correct value, how far off still counts, and the unit around it.
When to use it
Use a numeric answer when the result of a task is a number: a total, a measurement, the outcome of a formula. There is nothing to choose from, so students have to work the number out themselves.
If the answer is an expression or an equation rather than a single number, use a Math question instead.
Setting it up
In a worksheet, use the + between two items and choose Question.
Click the pencil to open it and write the question at the top, for example "A ticket costs 6 euros and the bus ride 9 euros. What does taking part cost in total?"
Set Answer format to Numeric.
Click Add correct answer and enter the value under Correct number.
Under Tolerance, enter how far an answer may be from that value and still count, for example 0.5. Leave it empty if only the exact number is right.
Click the tick when you are done.
Prefix and Suffix add text before or after the number. Fixed text shows a unit such as € or cm that students do not type. Fixed formula does the same for a unit written as a formula, such as m/s². Student enters gives students their own field for the unit; write the expected unit under Correct suffix or Correct prefix. Number placeholder sets the hint shown in the empty number field, and Add another accepted answer adds a second correct value.
What students do
Students see a number field, with your unit beside it if you fixed one, or a separate field for the unit if they are to enter it. They type the number and click Submit.
Checking the answers
Answers are checked automatically. An answer is correct when the number is within the tolerance of a correct value and the unit the student typed, if any, matches yours exactly. The right number with the wrong unit is partially correct.
Open Results on the question to see every answer, grouped with the students who gave it.
Tips
Set a tolerance whenever the answer comes from measuring or rounding. Without one, 2.49 does not count for 2.5.
Say in the question how to round, for example "to one decimal place", so the question and the tolerance agree.
Fix the unit when it is not what you are testing. Let students enter it when choosing the right unit is part of the task.