Chapter 1- Practice Set | Java Practice Problems With Solution

Chapter 1 – Practice Set

1. Write a program to sum three numbers in Java.
2. Write a program to calculate CGPA using marks of three subjects (out of 100)
3. Write a Java program that asks the user to enter his/her name and greets them with “Hello <name>, have a good day” text.
4. Write a Java program to convert Kilometers to miles.
5. Write a Java program to detect whether a number entered by the user is an integer or not.

Code as Described in the Video

package com.company;

import java.util.Scanner;

public class CWH_Ch1_PS {
    public static void main(String[] args) {
//        Question1
//        int a = 4;
//        int b = 17;
//        int c =6;
//        int sum = a + b+c;
//        System.out.println(sum);

//        Question2
//    float subject1 = 45;
//    float subject2 = 95;
//    float subject3 = 48;
//    float cgpa = (subject1 + subject2 +subject3)/30;
//    System.out.println(cgpa);

//        Question 3
//        System.out.println("What is your name");
//        Scanner sc = new Scanner(System.in);
//        String name = sc.next();
//        System.out.println("Hello " + name + " have a good day!");

//        Question 5
        System.out.println("Enter your number");
        Scanner sc = new Scanner(System.in);
        System.out.println(sc.hasNextInt());
    }

}

Solutions: 1. Write a program to sum three numbers in Java.

package com.company;

public class ch1practiceset {
    public static void main(String[] args) {
        int a=10;
        int b=15;
        int c=5;
        int sum=a+b+c;
        System.out.println(sum);
    }
}       


Output :

    30

2. Write a program to calculate CGPA using marks of three subjects (out of 100)

package com.company;

public class ch1practiceset {
    public static void main(String[] args) {
        float subject1=45;
        float subject2=95;
        float subject3=48;
                float cgpa=(subject1+subject2+subject3)/30;
        System.out.println(cgpa);
    }
}



Output :

        6.266667

3. Write a Java program that asks the user to enter his/her name and greets them with “Hello {name}, have a good day” text.

package com.company;

import java.util.Scanner;

public class ch1practiceset {
    public static void main(String[] args) {
        System.out.println("What is Your name ?");
        Scanner sc=new Scanner(System.in);
        String name=sc.next();
        System.out.println("Hello "+name+",have a good day");
    }
}

/*
Output :

  What is Your name ?
    Aryadeep
    Hello Aryadeep,have a good day */

4. Write a Java program to convert Kilometers to miles.

package com.company;

import java.util.Scanner;

public class ch1practiceset {
    public static void main(String[] args) {
        System.out.println("Kilometer to Miles Conversion");
        Scanner sc=new Scanner(System.in);
        System.out.println("Enter in Kilometers :");
        double a=sc.nextDouble();
        double convert=a*0.621371;
        System.out.println("Answer in Miles is : "+convert);
    }
}

/*

Output :

  Kilometer to Miles Conversion
Enter in Kilometers :
5
Answer in Miles is : 3.106855

 */

5. Write a Java program to detect whether a number entered by the user is an integer or not.

package com.company;

import java.util.Scanner;

public class ch1practiceset {
    public static void main(String[] args) {
        System.out.println("Enter the Number :");
        Scanner sc=new Scanner(System.in);
        System.out.println(sc.hasNextInt());
    }
}

/*
Output :

 Enter the Number :
45
true

Enter the Number :
ffggmm
false
 */