# The Tricky Viral Maths question 18 ÷ 3(5 - 4 + 1) = ? Solved and explained

Question 18÷3(5-4+1)=?

This Mathematics question is going viral on social media and class rooms etc. I personally had an argument with a friend on this same question. Many people are getting their answers as 3 or 12. I choose these two because they are the most common answers many people have. When I first saw this question online, I quickly pick my pen and paper, solve it and my answer was 3 then I was convinced that I got it right but I ask myself that why are some people having 12?. When I used a calculator, it also gives 12 meaning that my answer too was wrong. So, after I did a little research, I decided to write this article which will explain in details why some people have their answers as 3 while others have it as 12 and drawing conclusion on which one is really correct.

From other discussions, elsewhere and on social media many people justify their answers base on these two acronyms BODMAS and PEMDAS which are used in a concept in mathematics called Order of Operation.

PEMDAS is an acronym which stands for: Parenthesis or bracket, Exponent, multiplication, Division, Addition and Subtraction meanwhile BODMAS stands for: Bracket, Order of Operation, Division, Multiplication, Addition and Subtraction. Those who have 12 may say their answers is base on PEMDAS while those who have 3 may also say their answer is base on BODMAS but personally I and per the concept of Order of Operation, think whichever acronyms you use, will still give the same answer if you follow the basic mathematical algebraic rules and concepts.

The argument in this question according to social media is mainly base on whether to divide first or to multiply first and whether to state from right to left or from left to right. In basic mathematics they is a rule witch says all mathematical operations should be from left to right. If you use BODMAS, you will see that your answer will come out to be 12 but using PEMDAS following the acronym, your answer will be 3. This is simply because you multiply before you divide. The additional rule in mathematics which states that: "all operations in arithmetic should be done from left to right" now come into play. Follow the solving and explanations below kindly for better understanding.

From PEMDAS, (Have you ever heard of this? "Please Excuse Me Dear Aunt Sally!")

let 18÷3(5-4+1)= x

This implies that 18÷3(2)=x.

Secondly go to multiplication or division since they are no exponent. This is where the main argument come in. Those who use BODMAS has 12 because they solve with respect to the acronym even though some still has different answers with some obvious reasons but some who used PEMDAS may still have 3 if they multiply before dividing.

Therefore, PEMDAS is grouped into four steps with the third step having and additional rule which states that:
"all operations in mathematics are done from left to right". Here are the steps:
First; Parenthesis or Bracket
Second; Exponents
Third; multiplication or Division
From step three with the  left to right rule in solving, means that in this question, division is suppose to be done before multiplication.
So, 18 ÷ 3(2) = X,
18 ÷ 3 × 2 = x,
6 × 2=x,
12 = x,
X = 12. The answer is 12 because I followed mathematical rules but if I solve from the right, the answer will be as thus:
18 ÷ 3 × 2 = x,
18 ÷ 6 = x,
3 = x. This answer is fundamentally wrong. This is because in Math there are some basic roles that are generally accepted when solving problems.
Now use a scientific calculator to test your answers or see mind in the screen short below.