The Karnataka government launched the Bengaluru city logo- making Bengaluru the first Indian city to get its own logo - on 24 December 2017 for branding the city as a
A and B together can finish a work in 30 days. They worked for it for 20 days and then B left the work. The remaining work was done by A alone in 20 days more. In how many days can A alone finish the work?