SOLUTION: Mark has $100,000 to invest. His financial consultant advises him to diversify his investment in three types of bonds: short-term, intermediate-term, and long-term. The short-term

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Mark has $100,000 to invest. His financial consultant advises him to diversify his investment in three types of bonds: short-term, intermediate-term, and long-term. The short-term       Log On


   



Question 1205201: Mark has $100,000 to invest. His financial consultant advises him to diversify his investment in three types of bonds: short-term, intermediate-term, and long-term. The short-term bonds pay 4%, the intermediate-term bonds pay 5%, and the long-term bonds pay 6% simple interest per year. Mark wishes to realize a total annual income of 5.1%, with equal amounts invested in short- and intermediate-term bonds. How much should he invest in each type of bond?
short-term
intermediate-term
long-term

Found 2 solutions by ikleyn, josgarithmetic:
Answer by ikleyn(52805) About Me  (Show Source):
You can put this solution on YOUR website!
.
Mark has $100,000 to invest. His financial consultant advises him to diversify his investment
in three types of bonds: short-term, intermediate-term, and long-term.
The short-term bonds pay 4%, the intermediate-term bonds pay 5%, and the long-term bonds pay 6%
simple interest per year. Mark wishes to realize a total annual income of 5.1%,
with equal amounts invested in short- and intermediate-term bonds. How much should he invest in each type of bond?
short-term
intermediate-term
long-term
~~~~~~~~~~~~~~~~~~~~~~

x = short term;

x = intermediate term;

(100,000-2x) = long term.


Write the total annual interest equation

    0.04x + 0.05x + 0.06*(100000-2x) = 0.051*100000.


Simplify this equation and find x

    0.04x + 0.05x - 0.06*(2x) + 6000 = 5100

          -0.03x                      = 5100 - 6000

          -0.03x                     =    -900

                x                     = %28-900%29%2F%28-0.03%29 = 30000.


ANSWER.  $30,000 = short term;  $30,000 = intermediate term;  $100,000 - $30,000 - $30,000 = $40,000 = long term.

Solved.

Notice that three unknowns are found using one equation in one unknown.



Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Assuming investment for 1 year

              SIMPLE INT. RATE     QUANTITY Inv.      INTEREST earned

SHORT             4%                      x            0.04x

INTERMED.         5%                      x            0.05x

LONG              6%                  100000-2x       0.06(100000-2x)
 
Total             5.1%                 100000                        

Total interest
0.09x%2B0.06%2A100000-0.06%2A2x
0.09x-0.12x%2B6000
6000-0.03x

Wanting effective rate 5.1%
%286000-0.03x%29%2F100000=0.051
6000-0.03x=5100
0.03x=6000-5100
0.03x=900
3x=90000
highlight%28x=30000%29