Would you believe me if I told you... The snarky part of this problem is that both answers - 20 & 320 - can be considered correct. The real problem is that there is no single, definitive, universally-accepted mathematical rule for solving this problem. The correct solution depends on the context of the problem and how it is presented. This specific equation is problematic because it is presented with no context. Consequently, the answer could be the set of {20, 320}. It can also be argued that the answer could be a null set {} because the presentation of the equation is inadequate or incomplete and therefore unsolvable - to repeat a favorite Star Trek computer phrase, insufficient data. If we see it as an algebra problem, then we use: 4 * 4 + 4 * 4 + 4 - 4 * 4 16 + 16 + 4 - 16 20 PEMDAS Solve in this order: parenthesis exponentiation multiply and divide add and subtract working left to right There are two reasons for the popularity of PEMDAS: Algebra classes and EXCEL. However, it is not always an algebra problem, which means that PEMDAS is not always the correct method. If we see it as an arithmetic problem representing a sequence of calculations or events, then we solve each math operation in sequence, from left to right, as if a calculator was being used: 4 * 4 + 4 * 4 + 4 - 4 * 4 16 + 4 * 4 + 4 - 4 * 4 20 * 4 + 4 - 4 * 4 80 + 4 - 4 * 4 80 * 4 320 As is so often the case, context can be everything. The context in this case is deliberately ambivalent, unsettled, and unanswerable.
Posted on: Thu, 27 Mar 2014 14:33:37 +0000