If I invest £25,000 a year each year for 16 years and get a 5% return what will my total capital be ?

This is called a "sinking fund" although as we know it is rising

S = 25,000 [ (1+r)^n - 1 ]/r
here r = .05
n = 16

s = 25,000 * 23.657

= 591,437.29