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When three times a number is decreased by 7, the result is 20. What is the number?

The number is?

User Rvirding
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2 Answers

11 votes
3x-7=20
3x=27
x=9

number is 9
User DubyaDubyaDubyaDot
by
8.8k points
8 votes

Answer:

The number is 9

Explanation:

• Let the number be x


{ \tt{3x - 7 = 20}} \\

» Add 7 to either sides following addition rule of equality:


{ \tt{(3x - 7){ \red{ + 7}} = 20{ \red{ + 7}}}} \\ { \tt{3x = 27}}

» Divide either sides by 27:


{ \tt{ \frac{3x}{ \blue{3 }} = \frac{27}{ \blue{3}} }} \\ \\ { \tt{x = 9}}

User N Raghu
by
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