



 
Hi Adrian, What you have is \[50 + 9  13 \times 2\] where $\times$ is multiplication. I expect the question is do you read from left to write to get \[50 + 9  13 \times 2 = 46 \times 2 = 92\] or do you apply the multiplication first to get \[50 + 9  13 \times 2 = 50 + 9  26 = 33?\] This is a legitimate question so to eliminate this confusion mathematicians have agreed to always perform multiplication before addition or subtraction. Hence the correct answer is 33. If you want to write this so that the answer is 92 write the expression as \[(50 + 9  13) \times 2.\] The added punctuation, the parentheses, tell you to perform what is inside the parentheses first to get \[(50 + 9  13) \times 2 = 46 \times 2 = 92.\] Penny Adrian replied
Hi Again Adrian, I purposly rewrote your question as \[50 + 9  13 \times 2\] because I thought you had a mathematical expression to evaluate. The wording you sent "50+913 multiplied by 2=" is somewhat unusual because it mixes a mathematical expression with words as if it were an English sentence. If the question is to be understood as an English sentance "Fifty plus nine minus thirteen multiplied by two is what?" then I agree that you read the sentence from left to right obtaining an answer is nintytwo. If, as I expected, this question was to illustrate to students the importance of order of operations then the expression should be seen as \[50 + 9  13 \times 2\] and the mathematical conventions of order of operations used to obtain the answer 33. Penny  


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