SOLUTION: A SMALL CORPORATION BORROWED $800,000 TO EXPAND ITS LINE OF TOYS. SOME OF THE MONEY WAS BORROWED AT 8%, SOME AT 9%, AND SOME AT 10%. HOW MUCH WAS BORROWED AT EACH RATE IF THE ANN

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: A SMALL CORPORATION BORROWED $800,000 TO EXPAND ITS LINE OF TOYS. SOME OF THE MONEY WAS BORROWED AT 8%, SOME AT 9%, AND SOME AT 10%. HOW MUCH WAS BORROWED AT EACH RATE IF THE ANN      Log On


   



Question 111578: A SMALL CORPORATION BORROWED $800,000 TO EXPAND ITS LINE OF TOYS. SOME OF
THE MONEY WAS BORROWED AT 8%, SOME AT 9%, AND SOME AT 10%. HOW MUCH WAS
BORROWED AT EACH RATE IF THE ANNUAL INTEREST OWED WAS $67,000 AND THE
AMOUNT 8% WAS FIVE TIMES THE AMOUNT BORROWED AT 10%.

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
First, let's name the variables.
E=amount borrowed at 8%
N=amount borrowed at 9%
T=amount borrowed at 10%
Next, let's write down what you know.
1.Amount Borrowed : E%2BN%2BT=800000
2.Total Interest :+0.08%2AE%2B0.09N%2B0.10%2AT=67000
3.Relationship between E and T : E=5T
Let's substitute equation 3 into equations 1 and 2.
1. E%2BN%2BT=800000
1. 5T%2BN%2BT=800000
1. N%2B6T=800000
2. +0.08%2AE%2B0.09N%2B0.10%2AT=67000
2. +8E%2B9N%2B10T=6700000
2. +8%285T%29%2B9N%2B10T=6700000
2. +9N%2B50T=6700000
Now let's use equation 1 and solve for N in terms of T.
1. N%2B6T=800000
1. N=800000-6T
We can substitute that result into 2 and solve for T.
2. +9N%2B50T=6700000
+9%28800000-6T%29%2B50T=6700000
+7200000-54T%2B50T=6700000
+7200000-4T=6700000
+-4T=6700000-7200000
+-4T=-500000
+T=125000
From 1,
1. N=800000-6T
N=800000-6%28125000%29
N=50000
and from 3,
E=5T
E=5%28125000%29
E=625000
Let's check the answers.
E%2BN%2BT=800000
625000%2B50000%2B125000=800000
800000=800000
True statement.
+0.08%2AE%2B0.09N%2B0.10%2AT=67000
0.08%28625000%29%2B0.09%2850000%29%2B0.10%28125000%29=67000
50000%2B4500%2B12500=67000
67000=67000
True statement.
Your answers led to true statement.
They're good answers.
$625,000 borrowed at 8%
$50,000 borrowed at 9%
$125,000 borrowed at 10%