 Hi and welcome to the session. I'm Asha and I'm going to help you with the following question which says in a committee 50 people speak French, 20 speak Spanish and 10 speak both French and Spanish. How many speak at least one of these languages? So first let us see the one that if F and S are any two finite states such that they have some common elements the number of elements in F union S is equal to number of elements in the set F plus number of elements in the set S minus number of elements in the set F intersection S. So with the help of this formula, you will find the solution of the above problem. So this is a key idea. So to start with the solution let set of people who speak French be denoted by F and set of people who speak Spanish be denoted by. Then F intersection S will denote the set of people who speak both French and Spanish and according to the question we are given that number of people who speak French is equal to 50 number of people who speak Spanish is equal to 20 and the number of people who speak both the languages that is F intersection S is equal to 10. Now putting these values in the formula which is our key idea that is number of people who speak French or Spanish is equal to number of people who speak French plus number of people who speak Spanish minus the number of people who speak both is French and Spanish is equal to 50 plus 20 minus 10 which is equal to 70 minus 10 just further equal to 60. Thus we have N F union S is equal to 60. Thus we can say that number of people who speak one language is completes the solution. Hope you enjoyed it. Take care and have a good day.