PHOTOGABBLE // BLOG POST

Math Time

April 22nd, 2007

Okay, tell me what 2 -5 + 10 x 20 equals. Bonus points if you put the brackets where they aught to be, oh and cookie to whom ever can tell me what PEMDAS means

Well it’s morning time and only one person responded, I am not sure if they got it right though as this question was brought up in an online forum and within a couple of hours there where three different responses. PEMDAS is a simple way of remembering the logic behind arithmetic operations it goes: Parentheses, Exponents, Multiplication and Division, and Addition and Subtraction. These rules where created because the very question above; 2-5 + 10 x 20 has more than one answer if you break it down linearly you end up with 2 -5 = -3, -3 + 10 = 7, 7 x 20 = 140. However the correct answer is achieved with PEMDAS, multiplication is done first therefore we multiply ten by twenty to get two hundred. Next it’s addition which means we have to add -5 to 200, equalling 195. Then we have that two left all on its own, from what I remember every number either is negative or positive, so when written side by side it would be +2+195. When worked out that gives us 197 the true answer to this riddle.

I think I went about doing mine slightly differently to Weldo but it gave the same answer, silly math questions like this interest me and even though I pretty much fail at math I still find it entertaining; I guess I’m just odd

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3 Responses to “Math Time”

1. Weldo says:

   April 22, 2007 at 2:44 pm

   I came up with 197:
   (2-5) + (10×20)
   -3 + 200

   Reply
2. Sora says:

   April 22, 2007 at 3:53 pm

   Or you could use BIDMAS:
   Brackets, Indices, Division, Multiply, Addition and Subtraction

   I don’t understand the point in you bringing this up, but well done on working this out all by yourself ;P

   Reply
3. Mr Carbon Twelve says:

   April 30, 2007 at 3:05 am

   

   Reply