Question

有一个三位数减去它的各个数位的数字之和所得三位数为66x,求这个数字x

Answer 1

abc-(a+b+c)=66x,

100a+10b+c-a-b-c=66x,

99a+9b=66x,

9(11a+b)=66x,

66x是9的倍数,

66x/9=74,

x=6.