Instructor Help for Brownstone EDU - McGraw Hill Education ...

Specifying Precision
• To require that the student response exactly match the value of the correct answer (to
floating-point limits, approximately 8 decimal places), select Require absolute accuracy. For
example, if the correct answer is 2.77, the response 2.7701 is graded incorrect.
• To require that the student response contain a specific number of significant digits, and
exactly match the value of the correct answer, select # Figures, and then select the number of
significant digits from the drop-down box.
Example
Important: # Figures does not specify a margin of error. If you specify a correct
answer value in the answer value text field with more significant digits than the
number selected in the # Figures drop-down box, all student responses are graded
incorrect. For example, if you specify 2.771 as the correct answer value, and select
3 in the # Figures drop-down box, 2.77 is incorrect (because it does not have the
same value as the correct answer value 2.771) and 2.771 is incorrect (because it
has more than 3 significant digits).
In a physics problem, the correct answer is 2.70. If you insist that a student enter the correct number
of significant digits, you must use the # Figures option.
If you select Require absolute accuracy and enter 2.70 in the answer value text field, 2.7, 2.70,
and 2.700 are graded correct, which is not the desired behavior.
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