A tank can be filled by a pipe in 20 min. and by another pipe in 60 min. Both the pipes are kept open for 10 min. and then the first pipe is shut off. After this, the tank will be completely filled in__________? February 24, 2021 / By Preparation Point / Basic Maths Mcqs Share on WhatsApp Share on Facebook Share on Twitter Share on LinkedInA. 10 min B. 20 min C. 30 min D. 40 min Share this:TwitterFacebookMoreTelegramWhatsAppLike this:Like Loading... Related Share on WhatsApp Share on Facebook Share on Twitter Share on LinkedIn