Order of Addition, Subtraction
Date: 9/5/96 at 18:59:55 From: Anonymous Subject: The Order of Addition, Subtraction If an equation has both addition and subtraction in it, which do I solve first? An example is 24-3+9/3/3 or 7+4-3+1. Do you do all the addition before the subtraction in the second example or do you just go left to right? In the first example do you do the division first, then the addition, then the subtraction? This is confusing for me. Thanks, Karla
Date: 9/5/96 at 20:24:48 From: Doctor Robert Subject: Re: The Order of Addition, Subtraction Please Excuse My Dear Aunt Sally or PEMDAS is one way to remember the order of operations. P stands for parentheses. They should always be worked first. E stands for exponents. MD stands for multiplication/division done reading from left to right. One does not have priority over the other. AS stands for addition/subtraction reading from left to right. One does not have priority over the other. Your examples: 24-3+9/3/3 = 24-3+3/3= 24-3+1= 21+1= 22 7+4-3+1= 11-3+1= 8+1= 9 I hope that this helps. -Doctor Robert, The Math Forum Check out our web site! http://mathforum.org/dr.math/
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