Question 45867
<pre><font size = 3><b>$1800 is invested at 10% compounded quarterly for four years. Find the amount
at the end of four years. My answer is $2520.00 is this right, thank for
checking.

No, I'm afraid it's wrong.  You used the SIMPLE interest formulas i = Prt and
A = P + i.  You must consider the fact that this is COMPOUND interest, not
SIMPLE interest, and that the compounding is done 4 times a year.  You must 
use this COMPOUND interest formula instead:

A = P(1 + r/n)<sup>nt</sup>

where A = 1800, r = .10, n = 4 (for quarterly, 4 times per year), t = 4 (years)

A = 1800(1 + .10/4)<sup>(4×4)</sup> = 1800(1 + .025)<sup>16</sup> = 1800(1.025)<sup>16</sup> = 2672.110117

So your answer should be $2672.11

Edwin</pre>