** Using WeBWorK **

Hi Patricia,

There is a grader that does what you want and it works with reduced credit.

Look at custom_problem_grader_fluid in
/opt/webwork/pg/macros/PGgraders.pl

Here is an example of the code that goes in a .pg problem:

install_problem_grader(~~&custom_problem_grader_fluid);
$ENV{'grader_numright'} = [2,4];
$ENV{'grader_scores'} = [0.5,1];
$ENV{'grader_message'} = "You can earn " .
"50% partial credit for 2 - 3 correct answers.";

This example comes from The National Problem Library in directory FortLewis/Calc3/12-3-Contour-diagrams/HGM4-12-3-18a-Contour-diagrams/HGM4-12-3-18a-Contour-diagrams.pg. You should be able to find more examples there or search for "custom_problem_grader_fluid".

Arnie