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find the sum of the first 50 odd natural numbers by using arithmetic progression |
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Answer» 1,3,5 is correct in place 1,2,3 1,2,3.......a=1,d=2,n=50 S=n/2(2a+(n-1)d)S=50/2(2(1)+(50-1)2S=25(2+(49)2)S=25(2+98)S=25(100)S=2500 The first 50 natural odd numbers = 1,3,5,7... (upto 50 terms) which is an AP.Now, sn = n/2 [2a + (n-1)d]S50 = 50/2 [2x1 + (50-1)2]= 25 (2 + 98)= 25 x 100= 2500 |
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