Mathematical problems (solving linear equation with one variable) Xiaoming's telephone number is 7 digits, the first four digits are 6798, and the last three digits are three consecutive integers from small to large, and the sum of these three digits is twice the last digit

Mathematical problems (solving linear equation with one variable) Xiaoming's telephone number is 7 digits, the first four digits are 6798, and the last three digits are three consecutive integers from small to large, and the sum of these three digits is twice the last digit

Let these three digits be x, x + 1 and X + 2 respectively
X+X+1+X+2=2(X+2)
X=1
Xiaoming's phone number is 6798123