Answer :
Answer: 10%
Explanation:
The formula to calculate the simple interest (I) is given by :-
[tex]I=Prt---------(1)[/tex]
Final amount : [tex]A=P+I---------(2)[/tex]
Given : The simple interest earned on a certain amount is double the amount when invested for 10 years.
i.e A = 2P
Put this in equation (2), we get
[tex]2P=P+I\\\\\Rightarrow\ I=P[/tex]
Put the value of I in (1), we get
[tex]P=Prt\\\\\Rightarrow\ rt=1[/tex]
Since t=10 years {given} , then
[tex]r(10)=1\\\\\Rightarrow\ r=\dfrac{1}{10}=0.1[/tex]
In percent , [tex]r=0.1\times10=10\%[/tex]
Hence, the interest rate is being offered = 10%