CBSE Class 10: Sum of n Terms of an A.P. Videos | Arithmetic progression concepts

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• find the sum of following 6+13+20+....+97
• If the sum of the first n terms of an AP be n and the sum of first n terms be m then sum of its (m+n) terms is -(m+n)
• If the sum of first n,2n and 3n terms of an AP be S1 S2andS3 respectively then p3 S2-S1
• A contract on construction job specifies penalty for delay of completion beyond a certain date as follows Rs. 200 for 1st, Rs. 250 for 2nd, and Rs. 300 for 3rd, so on. If contractor pays Rs. 27,750 as penalty, find the number of days for construction work delayed.
• The sum of the first 7 terms of an AP is 63 and that of its next 7 terms is 161.find the AP
• If the pth term of an AP is 1/q and qth term 1/P. Prove that the sum of the first pqth term is 1/2 (pq + 1).
• if in an A.P. the sum of m terms equal to n and the sum of n terms is equal to m, then prove that the sum of (m+n) terms is -(m+n)
• find the sum of 8 multiple of 1.5
• find the sum of first 51 term of an AP whose second and third terms are 14 and 18 respectively.

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