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Find the sum of first fifty natural numbers |
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Answer» (1) 1+2+3+4+………………+48+49+50.If we start adding the first & the last numbers1+50= 512+49 = 513+ 48 = 514+ 47 = 51………..This way if we continue.. Towards the end we get…24 + 27 = 5125 + 26 = 51That shows, by adding them we get 51, 25 times.So the total will be 51 * 25 = 1275 . (2) So we can frame a formula now, whenever , the sum of first ’n’ numbers are to be found out…SUM = n/2 * (n+1) = 50/2*(50+1) = 25*51= 1275[3] or, The sum of any ‘n’ numbers = Sn =n/2 { 2a + (n-1)d} = 50/2 {(2+ 49*1}= 25*51= 1275 1275✌✌?? Emoji nhii Diya? Sorry bro my multiplication is wrong,emoji is correct and rest all r correct 25×51=1275? ... Ap:1,2,3.........Here a=1,d=1,n=50Sn=n/2[2a+(n-1)d]=50/2[2+(50-1)1]=25[2+49]=25(51)=2499 |
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