10 identical solid spherical balls of radius 3 cm are melted to form a single sphere. In this process 20% of solid is wasted. What is the radius (in cm) of the bigger sphere?
Raghuram sells a machine for Rs 43 lakhs at a loss. Had he sold it for Rs 53 lakh, his gain would have been 7 times the former loss. Find the cost price of the machine.