设原来的数十位是 x ,则个位是 10 - x
10x + 10 - x = 10(10 - x) + x - 18
9x + 10 = 82 - 9x
9x + 9x = 82 - 10
18x = 72
x = 4
十位 = x = 4
个位 = 10 - x = 6
所以这个两位数是 46