Есть девятиэтажный дом, в котором 4 подъезда

import java.util.Scanner;

public class Homework2 {
public static void main(String[] args) {
Scanner in =new Scanner(System.in);
System.out.println("Please type apt number: ");
int room=in.nextInt();
//int entrance=(room/(36+1))+1;
int entrance=(room-1)/36+1;
//int floor=(36/room)*9;
int floor=(room-1)%36/4+1;
if(room>=1&&room<=144){
System.out.println("Entrance: "+entrance);
System.out.println("floor: "+floor);
}
else{
System.out.println("Sorry Unfortunately we don’t have that room number info ");
}
}
}

Предложенное вами решение верно. Про форматирование кода уже писал.

import java.util.Scanner;

public class Practica {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        System.out.println("Please type apt number: ");
        int room = in.nextInt();
        int entrance = (room - 1) / 36 + 1;
        int floor = (room - 1) % 36 / 4 + 1;
        if (room >= 1 && room <= 144) {
            System.out.println("Entrance: " + entrance);
            System.out.println("floor: " + floor);
        } else {
            System.out.println("Sorry Unfortunately we don’t have that room number info ");
        }
    }
}

О вот теперь красота