Question 839029
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Hi,
Sam invested a certain amount of money{{{highlight_green(x)}}}  at 2.5% and $1800 more at 4%.
Question states***The annual interest that he earned was $150.
*** {{{.025x + .04(x+1800) = 150}}}
 {{{.025x + .04x+ 72 = 150}}}
       {{{.065x = 78}}}
              x = $1200, amt at 2.5%
Amount invested at 4% was $3000.    ($1200+ $1800)
CHECKING our answer***
 {{{.025*1200 + .04*3000)}}} = $30 + $120 =  $150
Wish You the Best in your Studies.