Image source: http://www.ci.anchorage.ak.us/iceimages/homepage/chef.gif
Restaurants and catering businesses that make food in volumes need to have
people that can rewrite recipes that are 5 to 100 times the original quantities.
For instance, a recipe of mashed potatoes that typically serves 4 might need
to be multipled by a factor of 6. If the recipe calls for 1/4 cup of garlic,
then they would need 6x1/4 cups = 6/4 cups. Instead of measuring 6 quarter-cups,
the restaurant can use the canceling property by factoring a 2 from the numerator
and denominator so that the expression is (3x2)/(2x2) = 3/2 cups or 1 1/2 cups.