14.1k views
2 votes
Two thirds a number plus 4 is 7

User Claudette
by
6.8k points

2 Answers

3 votes
Let "x" represent the "unknown number".

To write this as an equation:
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(⅔)x + 4 = 7 .
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To solve this equation (for "x") ;

Let us subtract "4" from EACH SIDE of the equation;

(⅔)x + 4 − 4 = 7 − 4 ;

to get:

(⅔)x = 3 ;

Now, multiple EACH SIDE of the equation by "3" (the denominator of the "fraction") ; to get rid of the "fraction" ;

3(⅔)x = 3*(3) ;

to get: 2x = 9 ;

Now, divide EACH SIDE of the equation by "2" ; to isolate "x" on one side of the equation; and to solve for "x" ;
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2x / 2 = 9 / 2

x = 9/2 = "4 ½ " ; or, write as: " 4.5" .
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User Stephen Brickner
by
7.1k points
3 votes
Lets call the number 'n'
plus means addition
is means the equal sign

so that as an expression would be
(2)/(3)n+4=7
User Klinger
by
6.6k points
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