Question 1205652
<pre>
FUND       RATE       AMT.INVT'D         PROFIT
  A         7%            x
  B         4%           x+6000
SUM                                       1780
</pre>
x assigned to amount in fund A, for sign convenience.


{{{0.07x+0.04(x+6000)=1780}}}

-

{{{0.07x+0.04x+(0.04)(6000)=1780}}}

{{{0.11x=1780-24*10^-2*10^3}}}

{{{0.11x=1780-240}}}

{{{x=(1780-240)/0.11}}}

{{{x=14000}}}---------------------Amount in fund B  is 6000 dollars more, so  {{{highlight(20000)}}}.