Question 103129
It is given that $ 4000 is invested at 6% 


So that we get $240. 



We will have to find What amount must be invested at 3% to make the total equals $270.


so 3 % of x = 30


==> {{{(3/100) * x =  30}}} 



==> 3x = 30 * 100


==> {{{x = (30 * 100)/3 }}} 


==> x = 1000 


So we must invest $ 1000 to make the total income equal to $270.


Thus the solution.


regards