Another pattern problem

So my friend show me this pattern the other day:

"So I'm gonna put 2000$ in the bank with an compound interest rate of 1.2% and then continue to put 2000$ annually

For the 0 year, I would get 2000$

For the 1st year ,I would get 2000(1.20)^1 +2000= 2400 + 2000 = 4400$

For the 2nd year, I would get 2000(1.20)^2 + 2000(1.20)^1 + 2000 = 2880 + 2400 + 2000 = 7,280$

For the 3rd year, I would get 2000(1.20)^3 + 2000(1.20)^2 + 2000(1.20)1 +2000 = 3,456 + 2880 + 2400 +2000 = 10736$ and so on.....

What would be in the nth year?"

I am confuse, please help me!

Easy Math Editor

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Comments

See geometric progression sum.

Pi Han Goh - 3 years, 7 months ago

Thanks so much, it helps!

A Former Brilliant Member - 3 years, 7 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$