Find the value of a 25 - a 15 for the A.P: 6,9,12,15,...........

This question is similar to Question 8 or 2nd CBSE Class 10 Sample Paper 2019 Boards

[Sample Paper Term 2] Find value of a25 − a15 for AP: 6, 9, 12, 15, - CBSE Class 10 Sample Paper for 2022 Boards - Maths Standard [Term 2]

part 2 - Question 1 (Choice 1) - CBSE Class 10 Sample Paper for 2022 Boards - Maths Standard [Term 2] - Solutions of Sample Papers for Class 10 Boards - Class 10

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Question 1 – Choice 1 Find the value of a25 − a15 for the AP: 6, 9, 12, 15, ……… Given A.P. 6, 9, 12, 15, ……… Thus, a = 6 & d = 9 − 6 = 3 We know that an = a + (n – 1) d Finding a25 and a15 Finding a25 a25 = a + (25 – 1) d a25 = a + 24d Putting a = 6, d = 3 a25 = 6 + 24 × 3 a25 = 6 + 72 a25 = 78 Finding a15 a15 = a + (15 – 1) d a15 = a + 14d Putting a = 6, d = 3 a25 = 6 + 14 × 3 a25 = 6 + 42 a25 = 48 Thus, a25 − a15 = 78 − 48 = 30

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo