If the fixed costs of a factory producing candles is Rs 20,000, selling price is Rs 30 per dozen candles and variable cost is Rs 1.5 per candle, what is the break-even quantity?
A boat goes 15 km upstream and 10 1/2 km down stream in 3 hrs 15 min. It goes 12 km upstream and 14 km downstream in 3 hrs. What is the speed of the boat in still water?