Merge pull request #1034 from gajennings/main

Fix bug 4754

Author: gajennings

OpenProblemLibrary/UVA-Stat/setStat212-Homework06/stat212-HW06-08.pg

@@ -11,7 +11,7 @@
 ## Institution(UVA)
 ## Author(Nolan A. Wages)
 ## Level(2)
-## Static(1)
+## MO(1)
 ## TitleText1('Statistics for Management and Economics')
 ## AuthorText1('Keller, Warrack')
 ## EditionText1('6')
@@ -24,54 +24,49 @@ DOCUMENT();        # This should be the first executable line in the problem.
 
 loadMacros(
   "PGstandard.pl",
-  "PGchoicemacros.pl",
-  "PGnumericalmacros.pl",
-  "PGstatisticsmacros.pl",
+  "MathObjects.pl",
   "PGcourse.pl"
 );
 
 TEXT(beginproblem());
 $showPartialCorrectAnswers = 1;
-## install_problem_grader(~~&std_problem_grader);
-
-$a = random(1,3,1);
-$b = random(6,10,1);
-$c = random(1,2,1);
-$d = random(5,7,1);
-$e = $c+1;
-$f = $d - 1;
-$g = $d - 2;
-
 
+Context("Numeric");
 
+$a = random(1,3,1);
+$p = $a + random(1,2,1);
+$q = $p + random(1,2,1);
+$r = $q + random(1,2,1);
+$b = $r + random(1,2,1);
+$w = $b-$a;
+$f = Compute("(x-$a)/$w");
+
+Context()->texStrings;
 BEGIN_TEXT
 $PAR 
 The following density function describes a random variable \(X\).
 
 $PAR
 \[
-f(x) = \frac{x - 1}{8} \;\;\mathrm{if}\;\; 1 < x < 5 
+f(x) = $f \;\;\text{if}\;\; $a < x < $b 
 \]
 $PAR
 
-A. Find the probability that \(X\) lies between 2 and 4.
+A. Find the probability that \(X\) lies between $p and $r.
 $PAR
 Probability =  \{ans_rule(15)\}
 $PAR
 
-B. Find the probability that \(X\) is less than 3.
+B. Find the probability that \(X\) is less than $q.
 $PAR
 Probability =  \{ans_rule(15)\}
 $PAR
 
-
-
-
-
 END_TEXT
+Context()->normalStrings;
 
-ANS(num_cmp(.5));
-ANS(num_cmp(.25));
+ANS(Compute("($r-$a)^2/$w^2-($p-$a)^2/$w^2")->cmp());
+ANS(Compute("($q-$a)^2/$w^2")->cmp());
 
 
 ENDDOCUMENT();       # This should be the last executable line in the problem.