Answer:
Please find below program
Step-by-step explanation:
import java.util.Scanner;
public class Tester {
 public static void main(String[] args) {
 
 // create an object of scanner class 
 Scanner scanner = new Scanner(System.in);
 
 //prompt user to enter first number 
 System.out.println("Enter first integer: ");
 
 // read value from entered by user and keep it in num1
 int num1 = scanner.nextInt();
 
 //prompt user to enter second number
 System.out.println("Enter second integer: ");
 
 // read value from entered by user and keep it in num2
 int num2 = scanner.nextInt();
 
 //prompt user to enter third number
 System.out.println("Enter third integer: ");
 
 // read value from entered by user and keep it in num3
 int num3 = scanner.nextInt();
 //close scanner as we have done with user input
 scanner.close();
 
 //calculate sum
 int sum = num1+num2+num3;
 
 //calculate average
 int average = sum/3;
 
 //calculate product
 int product = num1*num2*num3;
 
 //find out largest number
 int largest = 0;
 if (num1>=num2){
 if(num1>=num3)
 largest = num1;
 else
 largest = num3;
 }else {
 if(num2>=num3)
 largest = num2;
 else
 largest = num3;
 }
 
 // find out smallest number
 int smallest = 0;
 if (num1<=num2){
 if(num1<=num3)
 smallest = num1;
 else
 smallest = num3;
 }else {
 if(num2<=num3)
 smallest = num2;
 else
 smallest = num3;
 }
 
 // print all the information
 System.out.println("Sum of three numbers : "+sum);
 System.out.println("Product of three numbers : "+product);
 System.out.println("Average of three numbers : "+average);
 System.out.println("Smallest number : "+smallest);
 System.out.println("Largest number : "+largest);
 }
}