Question 45214
(x*.045)+(12000-x).04=525 or .045x+480-.04x=525 or .005x=525-480 or .005x=45 or

x=45/.005 or x=9000 invested @ 4.5% then 12000-9000=3000 invested @ 4%

proof 9000*.045+3000*.04=525 or 405+120=525 or 525=525