Question 1184144
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Justin and Darren had $1200 at first. Justin spent $400 while Darren
spent $120 less than him. The amount Darren had left was 3/5 of the
amount Justin had left. How much did Justin have at first?
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<pre>
Let x be the amount Justin had at first.

Then the amount Darren had at first was 1200-x dollars.



Justin spent 400 dollars; hence, his remainder is (x-400) dollars.

Darren spent (400-120) = 280 dollars;  hence, his remainder is  ((1200-x) - 280) = 920-x  dollars.



Next, the conditions says

    {{{Darren_remainder/Justin_remainder}}} = {{{3/5}}},

or

    {{{(920-x)/(x-400)}}} = {{{3/5}}}.



Cross multiply, simplify and find x


    5*(920-x) = 3*(x-400),

    4600 - 5x = 3x - 1200

    4600 + 1200 = 3x + 5x

       5800     = 8x

         x      = 5800/8 = 725.



<U>ANSWER</U>.  Justin had $725 at first.
</pre>

Solved.