问题
解答题
计算:1+11+21+…+1991+2001+2011=______.
答案
1+11+21+…+1991+2001+2011,
=(1+2011)×[(2011-1)÷10+1]÷2,
=2012×202÷2,
=203212.
故答案为:203212.
计算:1+11+21+…+1991+2001+2011=______.
1+11+21+…+1991+2001+2011,
=(1+2011)×[(2011-1)÷10+1]÷2,
=2012×202÷2,
=203212.
故答案为:203212.