.multiple {
  // Sass units that are multiplied and divided along with the values.
  multiple-numerators: inspect(1px * 1rad);
  multiple-denominators: inspect((1 / 1px / 1rad));
  divide-by-multiple-numerators: inspect(1 / (1px * 1rad));
  divide-by-multiple-denominators: inspect(1 / (1 / 1px / 1rad));

  // Units that appear in both the numerator and denominator cancel out, leaving
  // remaining units in place.
  $number: 1px * 1rad / 1ms / 1Hz;
  multiplication-cancels-denominator: inspect($number * 1ms);
  multiplication-cancels-denominator-twice: inspect($number * (1ms * 1Hz));
  multiplication-cancels-numerator: inspect($number * (1 / 1px));
  multiplication-cancels-numerator-twice: inspect($number * (1 / 1px / 1rad));
  multiplication-cancels-both: inspect($number * (1ms / 1px));
  division-cancels-numerator: inspect($number / 1rad);
  division-cancels-numerator-twice: inspect($number / (1px * 1rad));
  division-cancels-denominator: inspect($number / (1 / 1ms));
  division-cancels-denominator-twice: inspect($number / (1 / 1ms / 1Hz));
  division-cancels-both: inspect($number / (1px / 1ms));

  // Units cancel if they're compatible, even if they aren't identical.
  multiplication-cancels-compatible: inspect($number * 1s);
  division-cancels-compatible: inspect($number / 1in);

  // Units cancel even if they're totally unknown to Sass.
  $number: 1foo * 1bar / 1baz / 1qux;
  multiplication-cancels-unknown: inspect($number * 1baz);
  division-cancels-unknown: inspect($number / 1foo);
}