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# A number decreased by 30 is the same as 14 decreased by 3 times the number. Find the number. Explain!

A number decreased by 30 is the same as 14 decreased by 3 times the number. Find the number. Explain!

### 2 Answers by Expert Tutors

Nicholas M. | Friendly Tutor Here to Help Students Reach Their Full Potential!Friendly Tutor Here to Help Students Rea...
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x - 30 = 14 - 3x
4x = 44
x = 11
A number (x) decreased by 30 (x - 30) is the same as  (=) 14 decreased by 3 times the number (14 - 3x).
Philip P. | Effective and Affordable Math TutorEffective and Affordable Math Tutor
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Let's call the unknown number x

Now let's decrease it by 30, that is x-30

Now let's write out "14 decreased by three times the number", that is 14 - 3x

The problem says these are the same, that is x - 30 = 14 - 3x

We now want to isolate, or solve for, x

Move the x to one side of the equation by adding 3x to both sides

3x + x -30 = 14 - 3x + 3x

4x -30 = 14

Now move the 30 to the right hand side by adding 30 to both sides

4x - 30 + 30 = 14 + 30

4x = 44

Now all we have to do to get x is divide both sides by 4

4x/4 = 44/4

x = 11