Question 1151415
 ${{{10000 }}}is invested, part at {{{4}}}% and the rest {{{x}}} at {{{5}}}% interest. 

Let

{{{x}}} = amount in dollars invested at {{{4}}} %

{{{y}}}  = amount in dollars invested at {{{5}}} %


{{{x+y=10000}}}

{{{y=10000-x}}}......eq.1

Convert above information  into income.

 {{{I= P*R*T}}} (Interest = Principal * Rate* Time)

If you put{{{ x}}} in the bank at {{{4}}} %={{{0.04}}}, your interest would be {{{0.04x}}}
and {{{(10000-x) }}} at {{{5}}} %={{{0.05}}}, your interest earned from {{{5}}}% would be {{{0.05(10000-x) }}}

if the annual interest from the {{{4}}}% investment is ${{{40}}} more than that from the {{{5}}}% investment, we have

 {{{0.04x=0.05(10000-x)+40}}}

{{{0.04x=500-0.05x+40}}}

{{{0.04x+0.05x=500+40}}}

{{{0.09x=540}}}

{{{x=540/0.09}}}

{{{x=6000}}}

‭now find {{{y}}}

{{{y=10000-6000}}} ......eq.1

{{{y=4000}}} 


So, ${{{6000}}} was invested ‬at {{{4}}}%  and ${{{4000}}} at {{{5}}}% 

check annual interest:

$ {{{6000*0.04=240}}}   

$ {{{4000*0.05=200}}}   =>difference is  $ {{{40}}}