Solve this too

India
January 16, 2007 7:40am CST
1+2+3+4+........+10+11+......30=?
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3 responses
abhinavkumar1987
@abhinavkumar1987 (177)
• India
16 Jan 07
Its 465.Formula for summation of natural no. is n(n+1)/2
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mohanforu
@mohanforu (266)
• India
16 Jan 07
sUM OF first N natural numbers (n(n+1))/2 that leads to 465.
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deeshu
@deeshu (23)
• India
16 Jan 07
simple it's an arithmetic progresion where s=n\2(a+l) answer is 465