In an ap a 1 an 20 sn 399
WebAnswer : Let the required numbers in A.P.are (a - d), a and (a + d). Sum of these numbers = (a - d) + a + (a + d) = 3a Product of these numbers = (a - d)× a × (a + d)=a (a 2 - d 2) But given, sum = 24 and product = 440 ∴ 3a = 24 a = 8 and a (a 2 - d 2) = 8 (64 - d 2) = 440 [ a = 8] Or, 64 - d 2 = 55 Or, d 2 = 64 - 55 => d 2 = 9 => d = ± 3 WebIf an A.P. has a = 1, t n = 20 and s n = 399, then value of n is : A. 20 B. 32 C. 38 D. 40 Answer: Option C Solution (By Examveda Team) S n = 1 2 ( a + l) × n ⇒ 399 = ( 1 + 20) × n 2 ⇒ 399 × 2 = 21 × n ⇒ n = 399 × 2 21 ⇒ n = 19 × 2 ⇒ n = 38 Join The Discussion Related Questions on Progressions How many terms are there in 20, 25, 30 . . . . . . 140?
In an ap a 1 an 20 sn 399
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WebIf in an AP a = 1, t n = 20 and Sn = 399 then n is (a) 19 (b) 21 (c) 38 (d) 42 Report 497 Share Follow Answer peter Reputation: 2.6K University of Lagos, Nigeria 30 July 2024 … WebIf an A.P. has a = 1, t n = 20 and s n = 399, then value of n is : If an A.P. has a = 1, t. n. = 20 and s. n. = 399, then value of n is : A. 20. B. 32. C. 38.
WebQuestion If an AP has a = 1, a n = 20 and S n = 399, then find the value of n. Solution Compute the value of n: Formulae: The n th term of an AP is a n = a + n - 1 d and the sum of n terms of a series in an AP is S n = n 2 2 a + ( n - 1) d. Substitute a = 1, a n = 20 in the n th term of an AP formula. WebFeb 22, 2013 · In an A.P. , if a = 1, an= 20 and sn =399, then n is? Share with your friends 1 Follow 0 Jai Prakash, added an answer, on 22/2/13 we know from that formula that, Sn = n/2 (a + an) 399 = n/2 (1 + 20) 399*2 = n (21) n = 798/21 = 38 Therefore n = 38 Was this answer helpful? 3 View Full Answer
WebAug 25, 2024 · In an AP, if a = 1, an = 20 and Sn = 399, then n is equal to A. 19 B. 21 C. 38 D. 42. ← Prev Question Next Question →. 0 votes. 17.2k views. asked Aug 25, 2024 in … WebÿØÿî AdobedÀ ÿÛ„ ÿÀ € ÿÄØ !
WebWe can conclude that 10, 20, 30…, 500 is an AP with common difference, d = 10. First term, a = 10. Let the number of terms in this AP = n. Using nth term formula, an = a + (n – 1)d. 500 = 10 + (n – 1)10. 490 = (n – 1)10. n – 1 = 49. n = 50. Sum of an AP, Sn = (n/2) [ a + an], here an is the last term, which is given] = (50/2) ×[10 ...
WebLas protecciones eléctricas tienen un papel relevante en la seguridad y en la adecuada operación de un sistema eléctrico de potencia. Particularmente, en el caso de la generación y el trasporte, por su importancia requieren un eficiente sistema de protecciones que permita garantizar la integridad de sus elementos y la continuidad del servicio eléctrico. cinn buns recipeWebIn an AP if a = 1, a n = 20 and S n = 399, then n is 38. Explanation: ∵ S n = n 2 [ 2 a + ( n - 1) d] 339 = n 2 [ 2 × 1 + ( n - 1) d] 798 = 2 n + n ( n - 1) d ........ (i) And a n = 20 ⇒ a + ( n - 1) d = … dialects iowaWebSum of n terms of AP is given by: S n = n 2 2 a 1 + n-1 d where a 1 = first term, d = common difference. S 24-4 = 24-4 2 2 × 1 + 24-4-1 13 ∵ d = 13, n = 24, a 1 = 1 S 20 = 20 2 2 + 19 × 13 = 2490. a n-4 = a 1 + n-4-1 d a 24-4 = 1 + 24-4-1 13 ∵ d = 13, n = 24, a 1 = 1 a 20 = 248. Therefore, the ordered pair S n-4, a n-4 is equal to (2490 ... cinn cars trucksWebIn an AP, if a =1, an, = 20 and Sn = 399, then find n. ← Prev Question Next Question → +1 vote . 6.6k views. asked Feb 1, 2024 in Mathematics by Kundan kumar (51.5k points) In an … cinn childrens medical recordsWebFeb 11, 2013 · if an ap a=1 ,an=20,sn= 399 then n is Asked by anish mishra 11 Feb, 2013, 02:45: PM Expert Answer Sn=399 => n/2 (a + an) = 399 => n/2 ( 1 + 20) = 399 =>n/2 (21) = 399 => n = 399 X 2/21 => n= 38 Answered by 11 Feb, 2013, 05:49: PM Application Videos This video explains the concept of Arithmetic Progression, Solving Linear E... dialects in western visayasWebBesides giving the explanation of In an A.P. if a=1,An=20 and Sn=399, then find the value of n.?, a detailed solution for In an A.P. if a=1,An=20 and Sn=399, then find the value of n.? … cinn childrensWebFeb 26, 2016 · WE HAVE- SN=399 , A=1 & AN=20. {Sn=n/2 (a+an)} =>so lets substitute... 399=n/2 (a+an) 399=n/2 (1+20) 399=n/2 (21) =>lets send 2 and 21 to RHS. 399X2/21=n. … dialect sociolinguistics