Two pipes can fill a cistern in 28 and 21 hours respectively and an another pipe can empty 30 gallons of water per hour. All the three pipes working together can fill the empty cistern in 84 hours. What is the capacity (in gallons) of the cistern?
In a certain code language, '÷' represents '+', '-' represents 'x', '+' represents '÷' and 'x' represents '-'. Find out the answer to the following question.
Bhor Ghat was an ancient trade route developed by the Satavahana Dynasty to connect the ports on Konkan coast and surrounding areas of the Deccan plateau.