--description--

Objective: Fulfill the user stories below and get all the tests to pass to complete the lab.

User Stories:

1. You should have a function named getAverage that takes an array of test scores as a parameter and returns the average score.

2. You should have a function named getGrade that takes a student score as a parameter and returns a string representing a letter grade based on the score. Here are the scores and their corresponding letter grades:

   Score Range	Grade
   100	"A+"
   90 - 99	"A"
   80 - 89	"B"
   70 - 79	"C"
   60 - 69	"D"
   0 - 59	"F"

3. You should have a function named hasPassingGrade that takes a score as a parameter and returns either true or false depending on if the score corresponds to a passing grade.

4. The hasPassingGrade function should use the getGrade function to get the letter grade, and use it to determine if the grade is passing. A passing grade is anything different from "F".

5. You should have a function named studentMsg that takes an array of scores and a student score as the parameters. The function should return a string with the format:

   • "Class average: average-goes-here. Your grade: grade-goes-here. You passed the course.", if the student passed the course.
   • "Class average: average-goes-here. Your grade: grade-goes-here. You failed the course.", if the student failed the course.

   Replace average-goes-here with the average of total scores and grade-goes-here with the student's grade. Use getAverage to get the average score and getGrade to get the student's grade.

--hints--

You should have a function named getAverage.

assert.isFunction(getAverage);

Your getAverage function should return a number.

assert.isNumber(getAverage([92, 88, 12, 77, 57, 100, 67, 38, 97, 89]));

getAverage([92, 88, 12, 77, 57, 100, 67, 38, 97, 89]) should return 71.7.

assert.strictEqual(getAverage([92, 88, 12, 77, 57, 100, 67, 38, 97, 89]), 71.7);

getAverage([45, 87, 98, 100, 86, 94, 67, 88, 94, 95]) should return 85.4.

assert.strictEqual(getAverage([45, 87, 98, 100, 86, 94, 67, 88, 94, 95]), 85.4);

getAverage([38, 99, 87, 100, 100, 100, 100, 100, 100, 100]) should return 92.4.

assert.strictEqual(getAverage([38, 99, 87, 100, 100, 100, 100, 100, 100, 100]), 92.4);

getAverage([10, 20, 30, 40, 55, 65, 75, 83]) should return 47.25.

assert.strictEqual(getAverage([10, 20, 30, 40, 55, 65, 75, 83]), 47.25);

getAverage([10, 20, 30, 40, 50, 60, 70, 97]) should return 47.125.

assert.strictEqual(getAverage([10, 20, 30, 40, 50, 60, 70, 97]), 47.125);

Your getAverage function should return the average score of the test scores.

assert.strictEqual(getAverage([52, 56, 60, 65, 70, 75, 80, 85, 90, 95]), 72.8);
assert.strictEqual(getAverage([45, 50, 55, 60, 65, 70, 75, 80, 85, 90]), 67.5);
assert.strictEqual(getAverage([38, 42, 46, 50, 54, 58, 62, 66, 70, 74]), 56);

You should have a function named getGrade.

assert.isFunction(getGrade);

Your getGrade function should return "A+" if the score is 100.

assert.strictEqual(getGrade(100), "A+");

Your getGrade function should return "A" if the score is between 90 and 99.

assert.strictEqual(getGrade(90), "A");
assert.strictEqual(getGrade(94), "A");
assert.strictEqual(getGrade(99), "A");

Your getGrade function should return "B" if the score is between 80 and 89.

assert.strictEqual(getGrade(80), "B");
assert.strictEqual(getGrade(83), "B");
assert.strictEqual(getGrade(88), "B");

Your getGrade function should return "C" if the score is between 70 and 79.

assert.strictEqual(getGrade(70), "C");
assert.strictEqual(getGrade(75), "C");
assert.strictEqual(getGrade(79), "C");

Your getGrade function should return "D" if the score is between 60 and 69.

assert.strictEqual(getGrade(60), "D");
assert.strictEqual(getGrade(63), "D");
assert.strictEqual(getGrade(68), "D");

Your getGrade function should return "F" if the score is between 0 and 59.

assert.strictEqual(getGrade(0), "F");
assert.strictEqual(getGrade(30), "F");
assert.strictEqual(getGrade(43), "F");
assert.strictEqual(getGrade(59), "F");

You should have a function named hasPassingGrade.

assert.isFunction(hasPassingGrade);

Your hasPassingGrade function should return a boolean value.

assert.isBoolean(hasPassingGrade(100));

Your hasPassingGrade function should return true if the grade is an "A".

assert.isTrue(hasPassingGrade(100));

Your hasPassingGrade function should return false if the grade is an "F".

assert.isFalse(hasPassingGrade(53));

Your hasPassingGrade function should return true for all passing grades.

assert.isTrue(hasPassingGrade(87));
assert.isTrue(hasPassingGrade(60));
assert.isTrue(hasPassingGrade(73));
assert.isTrue(hasPassingGrade(96));

You should have a function named studentMsg.

assert.isFunction(studentMsg);

studentMsg([92, 88, 12, 77, 57, 100, 67, 38, 97, 89], 37) should return the following message: "Class average: 71.7. Your grade: F. You failed the course.".

assert.strictEqual(studentMsg([92, 88, 12, 77, 57, 100, 67, 38, 97, 89], 37), "Class average: 71.7. Your grade: F. You failed the course.");

studentMsg([56, 23, 89, 42, 75, 11, 68, 34, 91, 19], 100) should return the following message: "Class average: 50.8. Your grade: A+. You passed the course.".

assert.strictEqual(studentMsg([56, 23, 89, 42, 75, 11, 68, 34, 91, 19], 100), "Class average: 50.8. Your grade: A+. You passed the course.");

studentMsg([12, 22, 32, 42, 52, 62, 72, 92], 85) should return the following message: "Class average: 48.25. Your grade: B. You passed the course.".

assert.strictEqual(studentMsg([12, 22, 32, 42, 52, 62, 72, 92], 85), "Class average: 48.25. Your grade: B. You passed the course.");

studentMsg([15, 25, 35, 45, 55, 60, 70, 60], 75) should return the following message: "Class average: 45.625. Your grade: C. You passed the course.".

assert.strictEqual(studentMsg([15, 25, 35, 45, 55, 60, 70, 60], 75), "Class average: 45.625. Your grade: C. You passed the course.");

Your studentMsg function should return the correct message based on the student's score and the class average.

assert.strictEqual(studentMsg([33, 44, 55, 66, 77, 88, 99, 100], 92), "Class average: 70.25. Your grade: A. You passed the course.");
assert.strictEqual(studentMsg([33, 44, 55, 66, 77, 88, 99, 100], 57), "Class average: 70.25. Your grade: F. You failed the course.");

--seed--

--seed-contents--

--solutions--

function getAverage(scores) {
    let sum = 0;

    for (const score of scores) {
      sum += score;
    }

    return sum / scores.length;
  }

  function getGrade(score) {
    if (score === 100) {
      return "A+";
    } else if (score >= 90) {
      return "A";
    } else if (score >= 80) {
      return "B";
    } else if (score >= 70) {
      return "C";
    } else if (score >= 60) {
      return "D";
    } else {
      return "F";
    }
  }

  function hasPassingGrade(score) {
    return getGrade(score) !== "F";
  }

  function studentMsg(totalScores, studentScore) {
    let average = getAverage(totalScores);
    let grade = getGrade(studentScore);

    return `Class average: ${average}. Your grade: ${grade}. You ${
      hasPassingGrade(studentScore) ? "passed" : "failed"
    } the course.`;
  }