Question 1206221
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3/8 of the buttons are green. There were 20 more blue buttons than green. 
The remaining 84 buttons were pink. How many buttons were blue
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        It can be easily solved using only ONE unknown and one equation.
        See my solution below.



<pre>
Let x be the total number of buttons.

Then  {{{(3/8)x}}}  buttons are green;  {{{(3/8)x+20}}}  buttons are blue 
and remaining 84 buttons are pink.  


So, we can write this equation for total

    {{{(3/8)x}}} + {{{(3/8)x+20}}} + 84 = x.


At this point, the setup is complete.
To solve equation, multiply both sides by 8

    3x + 3x + 160 + 672 = 8x

    160 + 672 = 8x - 3x - 3x 

       832    =      2x

       x      =    832/2 = 416.


The number of blue buttons was  {{{(3/8)*416}}} + 20 = 176.    <U>ANSWER</U>
</pre>

Solved, using only one unknown.