The elements 'A' and 'B' combine together to give two compounds A2B3 and AB2. The weight of 0.2 mole of A2B3 is 26gm. The weight of 0.3 mole of AB2 is 24gm. Then the atomic weights of A and B respectively

Weight of 0.2 moles of A2B3 = 26gramsWeight of one mole of A2B3 = 130gramsGMW of A2B3 = 130g2A + 3B = 130.....(1)Weight of 0.3 moles of AB2 = 24gWeight of 1 moles of AB2 = 80gGMW of AB2 = 80gA + 2B = 80.....(2)Eq(1) 2A + 3B = 130Eq(2) ×2, 2A + 4B = 160.....(3)Eq(3) - Eq(1)B = 30Substituting the value of 'B' in Eq(1)2A + 3(30) = 130A = 20