void generateProblem() {
  String problemText = "";

  if (aStudy.known == 1) {
    problemText = aStudy.name + " claims that the average " + aStudy.obj + " in the US is " + aStudy.relation 
      + " " + nf(aStudy.muo, 1, 2) + " " + aStudy.unit + " with the population standard deviation of " 
      + nf(aStudy.sd, 1, 2) +  " " + aStudy.unit +". To verify this hypothesis, "+ aStudy.gender + " sampled "
      + aStudy.samplesize + " " + aStudy.noun + " and found a sample mean of " + nf(aStudy.mean, 1, 2) + " " + aStudy.unit 
      + ". What should " + aStudy.gender + " conclude?";
  } 
  else {
    problemText = aStudy.name + " claims that the average " + aStudy.obj + " in the US is " + aStudy.relation 
      + " " + nf(aStudy.muo, 1, 2) + " " + aStudy.unit +". To verify this hypothesis, "+ aStudy.gender + " sampled " 
      + aStudy.samplesize + " " + aStudy.noun + " and found a sample mean of " + nf(aStudy.mean, 1, 2) + " " + aStudy.unit 
      + " and a sample standard deviation of " + nf(aStudy.sd, 1, 2) + " " + aStudy.unit + ". What should "
      + aStudy.gender + " conclude?";
  }

  drawStrings(problemText, 30, 44, 25);

  testvalue = (aStudy.mean - aStudy.muo) * sqrt(aStudy.samplesize) / aStudy.sd;
}