The value would be 829.89.
The formula we use is
[tex]A=p(1+\frac{r}{n})^{nt}[/tex],
where A is the total amount, p is the principal, r is the rate expressed as a decimal number, n is the number of times per year the interest is compounded, and t is the number of years.
We will use 800 for p; 5.25/100 = 0.0525 for r; 365 for n; and (255/365) for t (since it is not a full year):
[tex]A=800(1+\frac{0.0525}{365})^{\frac{255}{365}\times365}
\\
\\=800(1+\frac{0.0525}{365})^{255}=829.89[/tex]
