Question 1180388
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<pre>

Let x be the number of rocks Robert has initially.


Then Caleb's amount is  {{{(2/9)x}}}  rocks.


After Robert lost 40 rocks, you have THIS EQUATION


    {{{(2/9)x}}} = 2*(x-40)


Simplify and solve


    2x = 9*2*(x-40)

    2x = 18*(x-40)

    2x = 18x - 720

    720 = 18x - 2x

    720 = 16x

     x  = 720/16 = 45.


<U>ANSWER</U>. Initially, Robert had 45 rocks.
</pre>

Solved, answered and carefully explained.


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@mananth setup the problem &nbsp;INCORRECTLY, &nbsp;so both his/her equation and the answer are &nbsp;WRONG.


For your safety, &nbsp;ignore his/her post.