To solve this question 0.03x+0.05 (6000-x)=220 Solve for x to know How much money was invested at 3% First multiply the values 0.03x+0.05×6000-0.05x=220 0.03x+300-0.05x=220 Second calculate the difference and rearranging the values 0.03x-0.05x=220-300 -0.02x=-80 Divide both sides by-0.02 and divide the values X=-0.02/-80 x=4000 invested at 3% this is the answer of your question