#### Answer

\[P=\frac{I}{rt}\].

#### Work Step by Step

The provided formula is\[I=P.r.t\] and now solve the formula for \[P\]by dividing both the sides by \[rt\].
\[\begin{align}
& I=P.r.t \\
& \frac{I}{rt}=\frac{P..}{} \\
& P=\frac{I}{rt}
\end{align}\]
The formula \[I=P.r.t\]is for simple interest, where \[I=\]interest earned on principal value, \[P=\]principal value, \[r=\]rate at which the interest is earned, and\[t=\]the time duration in which the interest is earned.
The formula is\[P=\frac{I}{rt}\].