In a bank principal increases at the rate of r% per year. Find the value of r if Rs. 100 double itself in 10 years `((log)_e2=0. 6931.)`

Explanation

Let Principal = p

given , principal increase as rate `r%` per year

`(dp)/(dt) = r% xx p`

`(dp)/(dt) = r/100 xx p`

`(dp)/(p) = r/(100) dt`

integrating on both side

`int(dp)/(p) = r/(100) int dt`

`logp =(rt)/(100) +logc`

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