2&3 =2+22+222 =246 3&4=3+33+333+3333=3702 9&4=?
问题描述:
2&3 =2+22+222 =246 3&4=3+33+333+3333=3702 9&4=?
答
2&3 =2+22+222 =246
3&4=3+33+333+3333=3702
规律:a&b=a+(10*a+a)+(10^2*a+10*a+a)+……+(10^b*a+……+10^2*a+10*a+a)
所以
9&4=9+99+999+9999=11106