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48÷2(9+3) = ?
Posted:
Jun 2, 2011 8:41 AM


This is an interesting problem I came across one day in searching for puzzling math problem and such (ie: 0/0) and it was surprising how big of an argument over the answer there is.
Basically, this can be looked at one of two ways:
The first way is using PEMDAS. However, considering that multiplication and division are on the same level (as is addition and subtraction), they can really go either way depending on the order. And since you do math left to right, it is assumed that you would do the division first. So it would be:
48/2 = 24 24(9+3) = 24(12) = 288
The second way is assuming that multiplication by juxtaposition takes precedence over the division, and therefor you would distribute the 2 first and then divide 48 by your answer. Using this, it would be:
2(9+3) = 2(12) = 24 48/24 = 2
I, personally, am very torn on this. My instinct tells me it's 2 but the reasoning I found for 288 is also very convincing. I would love to see some other opinions on this subject. :)



