Answer: C
For 3 years \((8-5)\), the interest amount is \((8200-7000)\) rupees = 1200 rupees
\(\therefore\) Interest for 1 year = \(\cfrac{1200}{3}=400\) rupees
\(\therefore\) Interest for 5 years = 400\(\times\)5 rupees
For 3 years \((8-5)\), the interest amount is \((8200-7000)\) rupees = 1200 rupees
\(\therefore\) Interest for 1 year = \(\cfrac{1200}{3}=400\) rupees
\(\therefore\) Interest for 5 years = 400\(\times\)5 rupees
= 2000 rupees
\(\therefore\) Principal amount = (7000-2000) rupees= 5000 rupees
\(\therefore\) Rate of interest \((r)=\cfrac{100\times I}{pt} \%\)\(=\cfrac{100\times 2000}{5000\times 5}\%\)
\(=8\%\)