Terry placed $15,000 in an account paying 6%. How much additional money should she deposit at 4% so that the average return on the two investments is 5.5%?

• Terry placed $15,000 in an account paying 6%, so 15,000(6%) = $900
  It was asked "how much additional" hence, we are going to add them.
  Let X be the additional money.
  
  Full solution:
  
  (15,000)(6%) + (4%)(X) = (5.5%)(15,000 + X)
  900 + 0.04X = 0.055(15,000) + 0.055X
  900 - 825 = 0.055X - 0.04X
  0.015X = 75 (divide both sides to 0.015, we will get...)
  X = $5000
  
  Hope this helps :)
• 3 years agoHelpfull: Yes(0) No(0)