 Hello and welcome to the session. In this session we discussed the following question which says the nth term of an AP is 7 minus 4n, find its common difference. Let's move on to the solution for this question. Let the nth term of an AP be equal to an and from the question we have that an is equal to 7 minus 4n. Then we have the common difference that we usually denote by D is equal to an that is the nth term minus an minus 1 that is n minus 1h term. Now as we have that an that is the nth term is 7 minus 4n so an minus 1 that is n minus 1h term would be equal to 7 minus 4 into n minus 1 which would be equal to 11 minus 4n. Thus we have the common difference D is equal to an that is 7 minus 4n minus an minus 1 that is 11 minus 4n. So this is equal to 7 minus 4n minus 11 plus 4n. Now this minus 4n plus 4n gets cancelled and we are left with 7 minus 11 which is equal to minus 4. So we get the common difference D is equal to minus 4. Hence our final answer is common difference is equal to minus 4. So this completes the session. Hope you have understood the solution of this question.