Question

$800 at 4.25% intrest for 6 years

Answer 1

To solve this (assuming that you mean simple interest) you need to first know the formula for exponential growth witch is S(1+(-)I)$^{T}$ so with all of are numbers inputed it looks something like this 800(1+.0425)$^{6}$ because,
S=starting amount, I=interest rate, and T=Time (amount of time that goes by) 
back to the equation it would equal 1027 (rounded to the nearest dollar)

Enjoy!=)

Answer 2

Idk if you are doing compound interest but here is simple:$1,004
you have to do 800 times 0.0425 times 6 and then add 800 to that answer. 
I = Prt