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1ãåå¼=29Ã(-12)+(3/4)Ã(-12)+290
=-348-9+290
=-357+290
=-67
2ãåå¼=13Ã(2/3)-(5/7)Ã(7/20)-(1/3)Ã(-13)-(2/7)Ã(7/20)
=13Ã(2/3)+(1/3)Ã13-(7/20)Ã[(5/7)+(2/7)]
=(1/3)Ã(26+13)-(7/20)
=13-(7/20)
=253/20
3ãåå¼=(1/3)[1-(1/4)]+(1/3)[(1/4)-(1/7)]+(1/3)[(1/7)-(1/10)]+â¦â¦+(1/3)[(1/2008)-(1/2011)]
=(1/3)[1-(1/4)+(1/4)-(1/7)+(1/7)-(1/10)+â¦â¦+(1/2008)-(1/2011)]
=(1/3)Ã[1-(1/2011)]
=(1/3)Ã(2010/2011)
=670/2011
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