The basic equation to use is y = abx but in this case the x is actually time, so let's use "t" as the variable. So y = abt
Also, the a is the initial value (starting point) so in this case, that is 3400. So, y = 3400bt
The b in this case is given by the interest rate. So convert 8.25% into a decimal (0.0825) but since this is growing by .0825, we actually need to add 1 to that decimal, so b = 1 + 0.0825 = 1.0825. That make the equation: y = 3400(1.0825)t.
But t = 25 years, so: y = 3400(1.0825)25
Just plug that into your calculator to get the value.