Find the rate of simple interest per annum when the interest of some money in 5 years will be \frac{2}{5} part of its principal.
WBBSE
Class X
Mathematics
Simple Interest
02 Mark
2023
Let the principal be P
SI = 2\over 5 of principal = 2\over 5 P
time (t) = 5 years
Rate = \text{SI} × 100\over \text{P × t} = {2\over 5}\text{P} × 100\over \text{P} × 5 = 8%
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