In a bank, principal increases continuously at the rate of r% per year. Find the value of r if Rs 100 double itself in 10 years (loge2 = 0.6931).
let t be time
p be principal
r be rate of interest
according the information principal increases at the rate of r% per year.
Separating variables,
Integrating both sides,
Given that t = 0, p = 100.
Now, if t = 10, then p = 2×100 = 200
So,
So r is 6.93%.