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Find the sum of first 30 natural nos. |
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Answer» Thank you all of you for your answers 1,2,3,4,5,6,...................... 30a=1d=1an =a+(n-1)d30=1+ n-1n=30S30 =15(2a+(29d)) = 30+29x15 = 30+435=465check ur answer s=n/2(a+L) = 15x31=465 ok =2a+(n-1)d=2×1+(n-1)1=2+n-1=-2=n-1=-2+1=n=-1=n Use formula 2a+(n-1)d |
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