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is ques ka ans aj tak koi nahi de paya.hello koi bataye bhai iska ans.1,6,7,13,20,......Sum upto 52 terms
Read Solution (Total 5)
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- 1+6+7+13+.....
=1+6+(1+6)+(1+6+6)+....
=1+6+1+(6+12+18+....up tp 50 terms)+(1+2+3+....49terms)
=8+6(1+2+3+....50 terms)+(1+2+3...49 terms)
=8+6((50*51)/2)+((49*50)/2)
=8+6(25*51)+(49*25)
=8+7650+1225
=8883 - 11 years agoHelpfull: Yes(10) No(4)
- Ans: 352849113670
1st and 2nd terms are 1,6
3rd term is 7 which is sum of first+second.
4th term is 13 which is sum of second + third.
Expanding the series further by adding a few more terms, it isÂ
1, 6, 7, 13, 20, 33, 53, 86, 139 and so on.
Now if we add the terms for upto 1,2,3,4,5,6 terms it isÂ
1, 7, 14, 27, 47, 80, 133, 219 and so on.
Hence we can infer the sum upto Nth term is (N+2)nd term - 6
As 1+6+7 is sum upto 3 terms and it is 5th term minus 6= 20-6 = 14
As 1+6+7+13+20+33+53 is sum upto 7 terms and it is 9th term minus 6 = 139-6 = 133
Hence sum upto 52nd term is nothing but 54th term -6.
Now our task is to find 54th term.
Using the golden ratio we can easily find the 54th term. But we will just find few more terms for accuracy.
1, 6, 7, 13, 20, 33, 53, 86, 139, 225, 364, 589, 953, 1542 which is upto 14 terms.
So 54th term = 1542 * (1.6180339)^40 = 352849113676 approx
Hence sum will be 352849113676-6 = 352849113670 - 11 years agoHelpfull: Yes(6) No(1)
- 1+6=7
6+7=13
7+13=20
like wise 13+20 = 33
20+33 = 53 (which is >52) so, ans is (1+6+7+13+20+33) = 80 - 11 years agoHelpfull: Yes(5) No(9)
- 1
6
1+6=7
7+6=13
20
33
53
86
139
225
364
589
953
1542
2495
4037
6532
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.52th term 352849113670 - 11 years agoHelpfull: Yes(2) No(0)
- Sum of the 52th term of fibonnaci series with 1st term 1 and 2nd term 6
- 11 years agoHelpfull: Yes(1) No(1)
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