Step-by-step explanation:
Let x be the principal amount.
Simple Interest Formula:
[tex]a = p(1 + rt)[/tex]
where a = final amount
p = principal amount
r = annual interest rate
t = time taken in years.
given a = 3x, p = x, t = 25, substitute a,p and t into formula.
[tex]3x = x(1 + 25r) \\ 1 + 25r = 3 \\ 25r = 3 - 1 \\ 25r = 2 \\ r = 2 \div 25 \\ = 0.08 \\ = (0.08 \times 100)percent \\ = 8percent[/tex]
8%*