 Hello and welcome to the session. I am Deepika here. Let's discuss the question which says a solid iron pole consists of a cylinder of height to 20 cm and base diameter 24 cm which is surmounted by another cylinder of height 60 cm and radius 8 cm. Find the mass of the pole given that 1 cm cube of iron has approximately 8 gram mass. Use pi is equal to 3.14. Now we know that volume of a cylinder is equal to pi e r square h where r is the radius and h is the height of this cylinder. Also mass is equal to volume into density. So this is the key idea behind our question. We will take the help of this key idea to solve the above question. So let's start the solution. Now according to the question a solid iron pole consists of a cylinder of height to 20 cm and the height of this cylinder is to 20 cm and base diameter 24 cm is surmounted by another cylinder of height 60 cm and radius 8 cm h1 be the radius height of first cylinder. This is our first cylinder and this is our second cylinder. Therefore this is equal to 24 upon 2 cm because the diameter is 24 cm and this is equal to 12 cm and h1 is equal to 220 cm. Therefore volume of first cylinder is equal to r1 square into h1. This is equal to take pi is equal to 3.14 into 12 square 20 cm cube. Let us take this as number 1. Let be the radius and height of second cylinder. Therefore r2 is equal to 6 cm and h2 is equal to 60 cm because it is given in the question also. Therefore volume of second cylinder is equal to 22 square into h2 and this is equal to 3.14 into 8 square into 60 cm cube. Let us give this as number 2. Now volume of the iron pole is equal to volume of first cylinder plus volume of second cylinder. Substitute the value of now from 1 volume of first cylinder is equal to 3.14 into 12 square is 144 into 220 plus 3.14 from 2 into 64 into 60 cm cube. Let us take 3.14 common. We have volume of the iron pole is equal to 3.14 into 144 into 220 plus 64 into 60 cm cube and this is equal to 3.14 into 31680 plus 3840 cm cube and this is again equal to 3.14 into 35520 cm cube. Now mass of 1 cm cube of iron is equal to 8 gram therefore mass of 3.14 into 35520 cm cube of iron is equal to into 3.14 into 35520 grams and this is equal to 1.4 upon 100 into 35520 upon 1000 kg because 1 kilogram is equal to 1000 grams. Want to convert grams into kilograms we will divide it by 1000. This is equal to 840 upon 1 land. In the fractional form we will convert this into decimal form. So this is equal to 2.26 kg. Answer for the above question is 892.26 kg. I hope the solution is clear to you. Bye and take care.