/= operator divides a variable by another number.
myVar = myVar / 5;
Will divide myVar by 5. This can be rewritten as:
myVar /= 5;
a, b, and c to use the /= operator.
a should equal 4
    testString: assert(a === 4, 'a should equal 4');
  - text: b should equal 27
    testString: assert(b === 27, 'b should equal 27');
  - text: c should equal 3
    testString: assert(c === 3, 'c should equal 3');
  - text: You should use the /= operator for each variable
    testString: assert(code.match(/\/=/g).length === 3, 'You should use the /= operator for each variable');
  - text: Do not modify the code above the line
    testString: assert(/var a = 48;/.test(code) && /var b = 108;/.test(code) && /var c = 33;/.test(code), 'Do not modify the code above the line');
```