A factory buys 7 machines. 2 MachineA, 4 MachineB and rest MachineC. Prices of the machines are Rs 56000, Rs 45000 and Rs 30000 respectively. Calculate the average cost of these machines.
In the following square represents Doctors, triangle represents Artists, circle represents Weight-lifters and rectangle represents Russians. Which set of letters represents Russians who are not Doctors?