Question 1151907
.
<pre>

The possible total of all future profits from this tool (assuming the tool lasts forever) is the sum of this infinite geometric progression


    400000*0.9 + 400000*0.9^2 + 400000*0.9^3 + . . . =  400000*(0.9 + 0.9^2 + 0.9^3 + . . . ) = {{{400000*(0.9/(1-0.9))}}} = {{{400000*(0.9/0.1)}}} = 

    = 400000*9 = 3600000 dollars.    <U>ANSWER</U>
</pre>