When creating an assessment, you can create a Formula assessment question in New Quizzes. In a Formula question, students need to type in the correct numerical answer.
Add Question Title and Stem
In the Question Title field , add a question title. Question titles are optional and are not visible to students.
In the Question Stem field , add the question stem. The question stem contains the question and, if necessary, additional instructions and information. You can use the Rich Content Editor to format and add content to your question stem.
Identify variables in your question by surrounding variable names by backticks. (e.g., a variable name of x can be identified by typing `x`.)
Add Variable Answers
After typing the question with the variable, parameters to define the formula will display . Set the variable answers for the formula. Specify the minimum  and maximum  values for the variable. Select decimal places in by using the increase or decrease arrows .
Add Formula Definition
Type the formula definition in the formula field. Make sure the formula does not contain any brackets or equal signs.
Notes: The Formula Definition supports the following operators: + (add), - (subtract), * (multiply), / (divide), and ^ (power).
Generate Possible Solutions
In the solution field, specify the number of possible solutions you want to generate .
In the error margin of field, enter the margin of error for the student's answer . Responses are based on relative error in addition to absolute error. Margins of error can be created as a percentage or as a point value (up to three decimal places).
To view possible solutions, click the Generate button .
View Possible Solutions
Possible solutions will process according to the number of value combinations.
To allow students to use an on-screen calculator for this question, click the Show on-screen calculator checkbox .
If you select this option, you can enable a basic calculator  or scientific calculator . The basic calculator displays numbers and basic math functions (add, subtract, multiply, divide). The scientific calculator displays more options for advanced calculations.
Note: The on-screen calculator option is intended to be used while displaying one question at a time. If the assessment does not display one question at a time, students may be able to use the calculator for all questions.
Align to Outcome
To align the question to an outcome, click anywhere in the Align to Outcomes section.
Add to Item Bank
If you want to save a question to use in other assessments, you can add it to an item bank.
To add the question to an item bank, click the Add to Bank link.
Note: After a question has been added to an item bank, it can only be edited in the item bank. You can still set unique point values and options in the assessment for an item bank question.
Add Point Value
To customize the point value for the question, type the point value in the Points field  or use the arrows to increase or decrease the point value .