设数列{an}和{bn}都是等差数列,且a1=25,b1=75,a100+b100=100,则数列{an+bn}的前10

数列{an+bn}的前100项和即为数列{an}和{bn}前100项和之和
s=(a1+a100)*100/2+(b1+b100)*100/2
=(a1+b1+a100+b100)*50
=10000