SOLUTION: the sum of three consecutive number is 18

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Question 1186311: the sum of three consecutive number is 18
Answer by ikleyn(52816) About Me  (Show Source):
You can put this solution on YOUR website!
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the sum of three consecutive number is 18. highlight%28Find_the_numbers%29.
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The numbers are (n-1), n, and (n+1).


Their sum is  (n-1) + n + (n+1) = 3n


We are given  3n = 18.


Hence,  n = 18/3 = 6.


So, the numbers are  5, 6, 7.


Check their sum:  5 + 6 + 7 = 18.   ! Correct !.


You just found the numbers, and the problem is just solved (!)

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Memorize this method (!)

Its idea is to consider the numbers  AROUND  the  CENTRAL  number.

Then you easily obtain that this central number is exactly one third of the sum.

As soon as you know it - - - you just know all three terms and the entire sequence  ( ! )

It is how  MATH  helps you solve problems  CORRECTLY,  quickly and elegantly  ( ! )  ( ! )


Happy learning with us  ( ! )


Come again soon  ( ! )


Next time,  do not forget to ask your question in your post.

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To see many other similar and different solved problems,  look into the lesson
    - Problems with consecutive integer numbers; odd even consecutive integer numbers
in this site.