Larry each rate.

Question

Larry invested part of his 26,000 advance at 2% annual simple interest and the rest at 3% annual simple interest. If his total yearly interest from both accounts was $760 , find the amount invested at each rate.

Answer 1

this is a 2 equations in 2 unknowns problem

Let x be the mount invested @ 2% and y the amount invested @ 3%

EQ 1

x + y = 26000

EQ2

0.02 x + 0.03 y = 760

 

from EQ1,

x = 26000 - y 

substitute in EQ2, you get

0.02 (26000 - y) + 0.03 y = 760

520 - 0.02 y + 0.03 y = 760

0.01 y = 240

y (the mount invested @ 3%) = $24,000

and

x (the mount invested @ 2%) = $2,000

Answer 2

x = amount invested at 2%

y = amount invested at 3%

 

x + y = 26,000

0.02x + 0.03y = 760

 

Solve this system of equations for x and y.  Try substitution.

 

x = 26,000 - y

0.02(26,000 - y) + 0.03y = 760

0.01y = 240

y = 240/0.01 = 24,000

x = 26,000 - y = 26,000 - 24,000 = 2,000

 

Larry invested $2,000 at 2% and $24,000 at 3%.