document.write( "Question 1137623: On January 1, 2000, $12,400 was deposited into an account that earns 2.55% interest compounded monthly. On January 1, 2010, $1,600 was deposited into the account and the bank changed the interest rate to 2.31% compounded monthly.
\n" );
document.write( "On January 1, 2014, $3,800 was withdrawn from the account and the interest rate was lowered to 1.99% compounded monthly.
\n" );
document.write( " a.) if no other deposits, withdrawals, or rate changes occur, how much money did the account have on January 1, 2020?
\n" );
document.write( " b.) Determine the total interest that was earned from January 1, 2000 to January 1, 2020? \n" );
document.write( "
Algebra.Com's Answer #755480 by Theo(13342)![]() ![]() You can put this solution on YOUR website! on january 1, 2000 you deposited 12400 earning 2.55% interest compounded monthly.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "on january 1, 2010, you deposited 4600 earning 2.31% compounded monthly.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "on january 1, 2014, you withdrew 3800 from the account and the interest rate was lowered to 1.99% compounded monthly.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "from january 1, 2000 to january 1, 2010 is 10 years.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "f = p * (1 + r) ^ n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "f is the future value \n" ); document.write( "p is the present value \n" ); document.write( "r is the interest rate per time period \n" ); document.write( "n is the number of time periods.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your timer periods are months.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "for the first segment between january 1, 2000 and january 1, 2010, you get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "p = 12400 \n" ); document.write( "n = 10 * 12 = 120 months. \n" ); document.write( "r = 2.55% / 100 = .0255 / 12 = .002125\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "formula becomes f = 12400 * (1 + .002125) ^ 120 = 15997.39535.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "on january 1, 2010, 1600 is added to this to get a total of 17597.39535.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "from january 1, 2010 to january 1, 2014, this is invested at the rate of 2.31% compounded monthly.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "f = p * (1 + r) ^ n becomes:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "f = 17597.39535 * (1 + .0231/12) ^ (4 * 12) = 19299.16978.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "on january 1, 2014, 3800 was withdrawn, leaving a balance of 15499.16978\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "this was invested from january 1, 2014 to january 1, 2020 at the annual rate of 1.99% compounded monthly.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "f = p * (1 + r) ^ n becomes:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "f = 15499.16978 * (1 + .0199/12) ^ (6 * 12) = 17463.05606.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "if i did this right, that should be what's in the account on january 1, 2020.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "i double checked through excel and it appears i did it right, at least if i did it right in excel.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "i think that's probably the answer you're looking for.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the amount in the account on january 1, 2020 = 17463.05606.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the total interest earned would probably be calculated as follows:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "on january 1, 2000 you deposited 12400.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "on january 1, 2010, this grew to 15997.39535.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "interest earned would be 15997.39535 minus 12400 = 3597.39535.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "on january 1, 2010, you had 17597.39535 in the account which grew to 19299.16978 on january 1, 2014.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "interest earned would be 19299.16978 minus 17597.39535 = 1701.77443.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "on january 1, 2014, you had 15499.16978 which grew to 17463.05606 on january 1, 2020.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "interest earned would be 17463.05606 minus 15499.16978 = 1963.88628.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "total interest earned was 3597.39535 + 1701.77443 + 1963.88628 = 7263.05606\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "i double checked this number through excel and it appears it is correct.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your solution should be:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "a.) if no other deposits, withdrawals, or rate changes occur, how much money did the account have on January 1, 2020? \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the amount in the account should be 17463.05606.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "b.) Determine the total interest that was earned from January 1, 2000 to January 1, 2020?\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the total interest earned should be 7263.056055.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |