A man invests $17,000 in two accounts. One account earns 5% interest per. year and the other earns 6.5& interest per year. If his total interest after one year is $970.00, how much did he invest in each account?

1 Answer
Feb 1, 2018

#1st " account"=$8,000.00#
#2nd " account"=$9,000.00#

Explanation:

  1. Assume variables for these two accounts;
    Let:
    x= the 1st account @ 5% per year
    y= the 2nd account @ 6.5% per year
    The other data provided in the problem are as follow:
    $17,000.00= the sum of the two accounts
    $970.00= the total interest of the two accounts
  2. Formulate equations from these accounts as provided in the problem; i.e.,
    #x+y=17,000->eq.1#
    #0.05x+0.065y=970->eq.2#

  3. Solve the equation simultaneously. Multiply the first equation by -0.05 to cancel the x variable to find the value of y as shown below.
    #x+y=17,000 color(red)}color(red)(-0.05#
    #ul(0.05x+0.065y=970)#
    #cancel(-0.05x)-0.05y=-850#
    #ul(cancel(0.05x)+0.065y=970)#
    #0.015y=120#
    #y=120/0.015#
    #y=8,000#

  4. Now, find the value of x using eq. 1.
    #x+y=17,000#
    #x=17,000-8,000#
    #x=9,000#

  5. Finally, the amount each account invested are;
    #x=$9,000.00#
    #y=$8,000.00#