 In this video, we are going to see how we can solve percentage problems. It could be any kind of problem and we will see how we can solve that. First of all, I would like you to create two parts of the page whenever you need to solve a problem. So let's just create two parts. Okay, on the left we will write total and on the right we will just write parts. On the left hand side, wherever we have written total, below that just write 100 and on the right hand side, we won't write anything for now. And now, let's read the problem. So on the left hand side, we have our space to work out the problem and on the right, let's just take any problem. The first kind of problem is like this. Find out 15% of 60. Now we are going to fill up the rest of the space here. So 15% means 15 out of 100. So if 100 is the total, the parts we are looking at is 15. And out of 60 means 60 is total. This is a critical information to get from here. You need to know what 60 is, if it is total or parts. We need to find 15% of 60 because we see off here, 60 is total. And we are interested in parts of 60 which is equal to 15%. So let me just put any variable here, say y. And now, we need to find out y from here. Once you arrange the numbers like this, you just simply need to cross-multiply and equate this. So if you cross-multiply, you get 100 y is equal to 60 times 15. And from here, y becomes 60 times 15 divided by 100. And that is equal to 9. And therefore, 9 is 15% of 60. Another kind of problem that we find in percentages of the type as follows. How many percent is 24 of 80? Now 80 is a total again. And out of it, we are looking at 24 parts of it. But we don't know how much percent it is or how many percent it is. So let's just assume some variable y again. And now, we will do cross-multiply again. So we multiply 80 with y. So 80y is equal to 24 times 100. And to solve for y, we get 2400 divided by 80. And that is 30. Because y is in the 100s row, we need to remember that it is percentage. And therefore, because y is 30, we can say that 24 is 30% of 80. Another kind of problem that we find is as follows. 36 is 12% of what? Now this what? Let's just make it a variable. Now we have 12% which will go into the parts column besides 100. 36 is 12%. 12% is in parts. So 36 will come along in parts. And we don't know the total for this case. And so we will put y in the total column. Now again, all we need to do is to cross-multiply and find y. Let's do that. 12 times y equals 36 times 100. Dividing both sides by 12, we can isolate y on the left. And we have 3600 divided by 12 which gives us 300. And so the total in this case has to be 300. And we can write the final answer as 36 is 12% of 300. And this is how we can solve different combinations of percentage problems for whatever unknown that has been given to us. All you need to know is where to write the known information in total or in parts and assume the variable for the correct quantity.