User talk:AlgebraKid

48 ÷ 2(9+3)= ? There are two answers, 2 and 288. If one strictly uses the standard order of operations to solve mathematical expressions, the answer to the problem would be 288, which is also the same solution provided by WolframAlpha and Google. By convention, the order of precedence in a mathematical expression is as follows: Terms inside of Brackets or Parentheses. Exponents and Roots. Multiplication and Division. Addition and Subtraction. If there are two or more operations with equal precedence (such as 10÷2÷5 or 7÷2*9), those operations should be done from left to right. Therefore, the problem “48÷2(9+3) =” would be solved like this: 48 ÷ 2 x (9+3) = 48 ÷ 2 x (12) = 48 ÷ 2 x 12 = 24 x 12 = 288

PEMDAS - Solving for the answer 2 is sometimes a result of doing multiplication before division. Much of the confusion can be blamed on PEMDAS (sometimes known as, “Please Excuse My Dear Aunt Sally”) and other similar mnemonics used to teach order of operations in schools. As an example, PEMDAS stands for: Parentheses Exponentiation Multiplication Division Addition Subtraction

Whereas BEDMAS stands for: Brackets Exponentiation Division Multiplication Addition Subtraction

The former can lead to the implication that addition always comes before subtraction, and that multiplication always comes before division. The latter can lead to the implication that addition always comes before subtraction, and that division always comes before multiplication. If one uses multiplication before division (PEMDAS being especially popular in the United States), the problem would be solved like this: 48 ÷ 2 * (9+3)= 48 ÷ 2 * (12)= 48 ÷ 2 * 12= 48 ÷ 24= 2 However, solving the problem like this would be considered erroneous because multiplication and division hold equal precedence. AlgebraKid (talk) 06:50, 22 April 2011 (UTC)