等差数列{an}中,已知公差d=1/2,且a1+a3+a5+···+a99=60.则a1+a2+a3+···+a100=

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等差数列{an}中,已知公差d=1/2,且a1+a3+a5+···+a99=60.则a1+a2+a3+···+a100=

a1+a3+a5+···+a99=60
a2+a4+···+a100=60+50*1/2=85
a1+a2+a3+···+a100=145

a1+a3+a5+···+a99
=(a1+a99)*50/2=60
a1+a99=2.4
a1+a100=a1+(a99+d)=2.4+1/2=2.9
a1+a2+a3+···+a100
=(a1+a100)*100/2
=145

要求的数的总和=已知数的总和*2+50d=60*2+25=145