SOLUTION: what is seven times a number plus the sum of three and twice anumber is 30 ?

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Question 759677: what is seven times a number plus the sum of three and twice anumber is 30 ?
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
x= the number in the problem

I see two possible interpretations.
The one I favor is:
seven times the number = 7x
twice the number = 2x
the sum of three and twice the number = 3%2B2x or 2x%2B3
seven times the number plus the sum of three and twice the number = 7x%2B2x%2B3=9x%2B3
"Seven times a number, plus the sum of three and twice the number is 30"
(interpreted with that comma) is the equation
7x%2B2x%2B3=30 or 9x%2B3=30
The solution to that equation is x=3 because
9x%2B3=30 --> 9x=30-3 --> 9x=27 --> x=27%2F9 --> x=3

The other interpretation does not have a pretty, integer number solution:
the sum of three and twice the number = 3%2B2x or 3x%2B2
the number plus the sum of three and twice the number = x%2B3%2B2x or 3x%2B3
Seven times that would be 7%283x%2B3%29 and if
"seven times (the number plus the sum of three and twice the number) is 30"
our equation would be
7%283x%2B3%29=30 --> 21x%2B3=30 --> 21x=30-3 --> 21x=27 --> x=27%2F21 --> x=9%2F7