Answer: in the second week, he had 138 customers
Step-by-step explanation:
Let w represent the number of customers in the 1st week
Let x represent the number of customers in the 2nd week
Let y represent the number of customers in the 3rd week
Let z represent the number of customers in the 4th week
The second week had 18 more customers than his first week. It means that
x = w + 18
The third week he had 4 less than twice as many as the second week. It means that
y = 2x - 4
The fourth week had 92. It means that
z = 92
If he had 382 customers, it means that
w + x + y + 92 = 382
w + x + y = 382 - 92 = 290 - - - - 1
Substituting w = 18 - x and y = 2x - 4 into equation 1, it becomes
18 - x + x + 2x - 4 = 290
2x = 290 - 14 = 276
x = 276/ 2 = 138