SOLUTION: I think of a number multiply it by 3 and then add 21 my answer is 74

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Question 1071844: I think of a number multiply it by 3 and then add 21 my answer is 74
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
I think of a number
I think of N
multiply it by 3
I get 3N
and then add 21
I get 3N+21
my answer is 74
I write 3N+21 = 74

So I have the equation

     3N+21 = 74

I add -21 to both sides to cancel the +21 on the left

  3N+21-21 = 74-21

        3N = 53

Then I divide both sides by 3 to cancel the 3

       %283N%29%2F3=53%2F3

         N = 53%2F3 or  17%262%2F3 

Edwin