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Double a number and add 12 and the result will be greater than 20. The number is less than 6. What is the number?

User Anders Sandvig
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1 Answer

27 votes
27 votes

The following expression is equivalent to "double a number and add 12":


2x+12

since the result is greater than 20, we have the following:


\begin{gathered} 2x+12>20 \\ \Rightarrow2x>20─12=8 \\ \Rightarrow x>(8)/(2)=4 \\ x>4 \end{gathered}

the number is also less than 6. Then we have that:

[tex]4therefore, the number is 5
User Anthony Rutledge
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