Question

(135 A $8000; p=*20000 L interest rate t= 12years compounded semiannually

Answer 1

Answer:

0.0778 (7.78%) is the interest rate

Step-by-step explanation:

Hello, great question. These types are questions are the beginning steps for learning more advanced Algebraic Equations.

Assuming I am understanding the question correctly (and the amount and principle are backwards), you are looking for the interest rate to make $20,000 with a initial deposit of $8000 in 12 years compounded semiannually. This being the case we can use the following Exponential Growth Formula and solve for the interest rate. The Formula is the one in the picture below.

$20,000 = 8,000(1+\frac{r}{2})^{2*12}$

$20,000 = 8,000(1+\frac{r}{2})^{24}$ .... divide both sides by 8000

$2.5 = (1+\frac{r}{2})^{24}$ .... sqr root to the 24th

$\sqrt[24]{2.5} = 1+\frac{r}{2}$

$1.0389 = 1+\frac{r}{2}$ ... subtract 1 on both sides

$0.0389 = \frac{r}{2}$ .... multiply 2 on both sides

$0.0778 = r$ ...rounded up

Finally, we can see that 0.0778 (7.78%) is the interest rate

** IF the question was written correctly and the Amount is smaller than the initial deposit, then you can just switch both values and solve for r again, it will give you a negative interest rate. **

I hope this answered your question. If you have any more questions feel free to ask away at Brainly.