find the sum of series 12+14+16 ...220
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Step-by-step explanation:
= 12+14+16+18+20+....+220
= 2+4+6+8+10+12+14+16+18...+220 - (2+4+6+8+10)
= 2(1+2+3+4+5+6+...+110) - 2(1+2+3+4+5)
we know formula of sum of AP = n(n+1)/2
= 2*(110*111)/2 - 2*(5*6)/2
= 12,210 - 30
= 12,180
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