When Geeta increases her speed from \(12\) km/hr to \(20\) km/hr, she takes one hour less than the usual time to cover the distance between her home and office. What is the distance, in kilometres,…

The home-to-office distance is $30$ km. For a distance $d$, the time saved is $\frac{d}{12}-\frac{d}{20}=\frac{d}{30}$ hours, so a saving of one hour gives $d=30$. A result of $15$ km would give a saving of half an hour.