Ex 5.3, 1 Class 10 (NCERT Solutions) - Find sum of APs (i) 2, 7, 12,

Ex 5.3, 1 - Chapter 5 Class 10 Arithmetic Progressions - Part 2

Ex 5.3, 1 - Chapter 5 Class 10 Arithmetic Progressions - Part 3 Ex 5.3, 1 - Chapter 5 Class 10 Arithmetic Progressions - Part 4

Ex 5.3, 1 - Chapter 5 Class 10 Arithmetic Progressions - Part 5 Ex 5.3, 1 - Chapter 5 Class 10 Arithmetic Progressions - Part 6

Ex 5.3, 1 - Chapter 5 Class 10 Arithmetic Progressions - Part 7 Ex 5.3, 1 - Chapter 5 Class 10 Arithmetic Progressions - Part 8 Ex 5.3, 1 - Chapter 5 Class 10 Arithmetic Progressions - Part 9

  1. Chapter 5 Class 10 Arithmetic Progressions
  2. Serial order wise

Transcript

Ex 5.3, 1 Find the sum of the following APs. (i) 2, 7, 12 ,โ€ฆ., to 10 terms. 2, 7, 12,โ€ฆ., to 10 term s We know that Sum of AP = ๐‘›/2 (2a + (n โ€“ 1) d) Here n = 10, a = 2, & d = 7 โ€“ 2 = 2 Putting these in formula , Sum = ๐’/๐Ÿ (2a + (n โ€“ 1) d) = 10/2 (2 ร— 2 + (10 โ€“ 1) ร— 5) = 5(3 + 9 ร— 5) = 5 (4 + 45) = 5 (49) = 245 Ex 5.3, 1 Find the sum of the following APs. (ii) โˆ’37, โˆ’33, โˆ’29 ,โ€ฆ, to 12 terms โ€“37, โ€“33, โ€“29 ,โ€ฆ, to 12 terms We know that Sum = ๐‘›/2 (2a + (n โ€“ 1)d) Here n = 12, a = โ€“37 & d = โ€“ 33 โ€“ (โ€“37) = โ€“ 33 + 37 = 4 Putting values in formula Sum = ๐’/๐Ÿ (2a + (n โ€“ 1) d) = 12/2 (2 ร— (โ€“37) + (12 โ€“ 1) ร— 4) = 6 (โ€“74 + 11 ร— 4) = 6 (โ€“74 + 44) = 6 (โ€“30) = โ€“180 Ex 5.3, 1 Find the sum of the following APs. (iii) 0.6, 1.7, 2.8 ,โ€ฆโ€ฆ.., to 100 terms 0.6, 1.7, 2.8,โ€ฆโ€ฆ to 100 terms We know that Sum = ๐‘›/2 (2a + (n โ€“ 1) d) Here n = 100, a = 0.6, & d = 1.7 โ€“ 0.6 = 1.1 Putting in formula Sum = ๐’/๐Ÿ (2a + (n โ€“ 1) d) = 100/2 (2 ร— 0.6 + (100 โ€“ 1) ร— 1.1) = 50(1.2 + 99 ร— 1.1) = 50(1.2 + 108.9) = 50 (110.1) = 50 ร— 110 . 1 = 5505 Ex 5.3, 1 Find the sum of the following APs. (iv) 1/15, 1/12, 1/10 ,โ€ฆโ€ฆโ€ฆ, to 11 terms 1/15, 1/12, 1/10, โ€ฆ.. to 11 terms We know that Sum = ๐‘›/2 (2a + (n โ€“ 1) d) Here n = 11 , a = 1/15 & d = 1/12 โ€“ 1/15 = (15 โˆ’ 12)/(12 ร— 15) = 3/180 = 1/60 Putting values in formula Sum = ๐’/๐Ÿ (2a + (n โ€“ 1) d) = 11/2 ("2 " ร—" " 1/15 " + (11 โ€“ 1) " ร—" " 1/60) = 11/2 (2/15 " + 10 " ร— 1/60) = 11/2 (2/15 " + " 10/60) = 11/2 ((2 ร— 4 + 10)/60) = 11/2 ((8 + 10)/60) = 11/2 ร— 18/60 = 11 ร— 9/60 = 11 ร— 3/20 = ๐Ÿ‘๐Ÿ‘/๐Ÿ๐ŸŽ

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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 10 years. He provides courses for Maths and Science at Teachoo.