Merge pull request openwebwork#1169 from gajennings/main

Fix bug 4837, convert to PGML, add solution

Author: gajennings

OpenProblemLibrary/NAU/setProbability/ExpValueProbModel1.pg

@@ -17,44 +17,60 @@ DOCUMENT();        # This should be the first executable line in the problem.
 
 loadMacros(
   "PGstandard.pl",
-  "PGchoicemacros.pl",
-  "PGgraphmacros.pl",
+  "MathObjects.pl",
+  "PGML.pl",
+  "niceTables.pl",
   "PGcourse.pl"
 );
 
-TEXT(beginproblem());
-$showPartialCorrectAnswers = 1;
+Context("Numeric");
 
+@seq=();
+for (0..12){
+  push @seq, $_/2;
+}
+
+@out = random_subset(4,@seq);
 
-@out=();
-push @out, random(0,6,.5) foreach 0..3;
 @outcome=num_sort(@out);
 
 $a=random(0.05,.40,.05);
 $b=random(0.05,.40,.05);
-$ans1=1-$a-$b-0.15;
+$ans1=Real(1-$a-$b-0.15);
 @prob=($a,$b,0.15,$ans1);
 
 
-$ans=0;
+$ans2=0;
 for($i=0; $i<4; $i++){
-    $ans=$ans+$outcome[$i]*$prob[$i];
+    $ans2=$ans2+$outcome[$i]*$prob[$i];
 }
+$ans2=Real($ans2);
+
+$tab = DataTable(
+ [
+    ["Outcome", $outcome[0], $outcome[1], $outcome[2], $outcome[3]],
+    ["Probability", $prob[0], $prob[1], $prob[2], ans_rule(5)]
+ ],
+ horizontalrules => 1,
+ texalignment => 'l|c|c|c|'
+);
+
+BEGIN_PGML
+
+Below is a partially complete probability model. Enter the probability for the final outcome.
+
+[@ $tab @]* 
+
+Find the expected value of the probability model.  [__]{$ans1}{30}
+END_PGML
 
-BEGIN_TEXT
+ANS($ans2->cmp());
 
-Below is a partially complete probability model. Enter the probability for the final outcome. $BR
-\{begintable(9)\}
-\{row("Outcome", $outcome[0], $outcome[1], $outcome[2], $outcome[3])\} 
-\{row("Probability", $prob[0], $prob[1], $prob[2], ans_rule(5))\} 
-\{endtable()\}  $BR $BR
-Find the expected value of the probability model. $BR  $BR
-\{ans_rule(30)\}
-$BR
-END_TEXT
+BEGIN_PGML_SOLUTION
+The probabilities must add up to 1, so the probability that the outcome equals [$outcome[3]] is 1-([$prob[0]]+[$prob[1]]+[$prob[2]]) = [$ans1] .
 
-ANS(num_cmp($ans1));
-ANS(num_cmp($ans));
+The expected value is ([$prob[0]])([$outcome[0]])+([$prob[1]])([$outcome[1]])+([$prob[2]])([$outcome[2]])+([$ans1])([$outcome[3]])=[$ans2] .  
+END_PGML_SOLUTION
 
 ENDDOCUMENT();       # This should be the last executable line in the problem.