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14 votes
14 votes
If Bill

deposits $3000 in an account that earns 6.5% compound interest annually for 3.5 years.
How much interest will he have earned?

User Dario Pellegrini
by
2.8k points

1 Answer

16 votes
16 votes

Answer:

$3,623.84 Exact answer without rounding | $3,623.85 ~ (Approximent Answer with rounding.)

Explanation:

Compound Interest Has a Specific Formula:

This case is Exponential Growth.

Formula: y= ab^x

You need to set up the equation.

First we need to define the rate of growth meaning what do you have to do for the 6.5%.

You need to do 100% + 6.5% = 106.5%

You need to convert the percent to a decimal which will be 1.065


Now we need to start plugging things into our formula to solve.

Your initial Starting amount was $3000

So you need to have y=3000(b)^x

We now know that the rate of growth is 1.065 so the b would be 1.065

y=3000(1.065)^x

Our power to x is our 3.5 years.

Our Equation now:

y=3000(1.065)^3

Now you need to use a calculator to do this due to the amount of decimals and digits.

Remember pemdas when doing this!!!

The answer should result to $3,623.84 but if rounded then: $3,623.85

User Guillo
by
2.4k points