   SEARCH HOME Math Central Quandaries & Queries  Question from Kam, a parent: Your store guidelines states that when Actual Food Cost is 3% or more above Projected Food Cost, immediate corrective action be taken by the Unit Manager. In January, your Actual Food Cost was $11,000, and your Projected Food Cost was$10,850. To find out what percentage the difference is do I divide the difference ($150) by Actual Food Cost ($11,000) or Projected Food Cost (\$10,8500)? What would be the answer? Thanks Kam,

This is a problem with the way we use the term percentage. Whenever we say percentage we should say percentage of what. In this case I expect what is intended is that the store manager determines the projected food cost and then adds 3% of this cost to determine the actual food cost. Thus

(actual food cost - projected food cost)/(projected food cost) should be at least 0.03.

Harley     Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.