JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 439 · 40 questions

Code tip (Line by line): let x = 5; makes a variable x holding 5; x = x + 2; changes it to 7. console.log(…) writes in the console; alert(…) shows a pop-up box. Text in quotes + anything = joined text: "5" + 3 → "53".

1. 1.⚡ What does this code print? (Look at the quotes!)
   let x = "7";
   let y = 5;
   console.log(x + y); (a) Error (b) 12 (c) 75
2. 2.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <code> (c) <style> (d) <script>
3. 3.⚡ What number does this code print?
   let a = 3;
   let b = 3;
   console.log(a * b);
4. 4.⚡ What number does this code print?
   let apples = 8;
   apples = apples + 4;
   apples = apples - 4;
   console.log(apples);
5. 5.⚡ What does this code show?
   let name = "Arjun";
   console.log("Hello, " + name + "!"); (a) Arjun (b) Hello, name! (c) name (d) Hello, Arjun!
6. 6.⚡ What number does this code print?
   let a = 33;
   let b = 25;
   console.log(a + b);
7. 7.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .css (c) .js (d) .html
8. 8.⚡ What number does this code print?
   let marks = 30;
   marks = marks + 5;
   marks = marks - 32;
   console.log(marks);
9. 9.⚡ What does alert() show? (a) a table (b) a new tab (c) a pop-up box (d) a picture
10. 10.⚡ What number does this code print?
    let books = 30;
    books = books + 6;
    books = books - 19;
    console.log(books);
11. 11.⚡ What does JavaScript add to a web page? (a) the page title (b) the domain name (c) actions and changes (d) only colours
12. 12.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) if (c) for (d) console.log()
13. 13.⚡ What number does this code print?
    let apples = 7;
    apples = apples + 13;
    apples = apples - 1;
    console.log(apples);
14. 14.⚡ Which JavaScript word writes in the console? (a) for (b) if (c) console.log() (d) alert()
15. 15.⚡ Which word makes a new variable? (a) give (b) make (c) put (d) let
16. 16.⚡ Where does console.log() show its output? (a) in the console (b) on the title bar (c) in the address bar (d) on the printer
17. 17.⚡ What does this code show?
    let name = "Arjun";
    alert("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Welcome, Arjun! (d) Arjun
18. 18.⚡ Which JavaScript word runs code when true? (a) alert() (b) console.log() (c) if (d) let
19. 19.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!"); (a) Hello, Kabir! (b) name (c) Hello, name! (d) Kabir
20. 20.⚡ What number does this code print?
    let a = 8;
    let b = 5;
    console.log(a - b);
21. 21.⚡ Which JavaScript word repeats code? (a) alert() (b) for (c) console.log() (d) let
22. 22.⚡ What number does this code print?
    let a = 36;
    let b = 31;
    console.log(a - b);
23. 23.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 7;
    console.log(x + y); (a) 8 (b) 17 (c) Error
24. 24.⚡ What number does this code print?
    let score = 5;
    score = score + 19;
    score = score - 21;
    console.log(score);
25. 25.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) Riya (b) Hi, name! (c) name (d) Hi, Riya!
26. 26.⚡ What number does this code print?
    let marks = 9;
    marks = marks + 14;
    marks = marks - 20;
    console.log(marks);
27. 27.⚡ What number does this code print?
    let a = 9;
    let b = 6;
    console.log(a * b);
28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 7;
    console.log(x + y); (a) 15 (b) Error (c) 87
29. 29.⚡ What number does this code print?
    let a = 4;
    let b = 4;
    console.log(a * b);
30. 30.⚡ What number does this code print?
    let a = 20;
    let b = 11;
    console.log(a + b);
31. 31.⚡ What does this code show?
    let name = "Zoya";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) Zoya (c) name (d) Well done, Zoya!
32. 32.⚡ What number does this code print?
    let a = 9;
    let b = 7;
    console.log(a * b);
33. 33.⚡ What number does this code print?
    let marks = 7;
    marks = marks + 18;
    marks = marks - 1;
    console.log(marks);
34. 34.⚡ What does this code show?
    let name = "Aman";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) Welcome, Aman! (c) name (d) Aman
35. 35.⚡ What number does this code print?
    let apples = 6;
    apples = apples + 4;
    apples = apples - 1;
    console.log(apples);
36. 36.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 4;
    console.log(x + y); (a) 6 (b) Error (c) 24
37. 37.⚡ What number does this code print?
    let score = 12;
    score = score + 12;
    score = score - 6;
    console.log(score);
38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 4;
    console.log(x + y); (a) Error (b) 14 (c) 5
39. 39.⚡ What number does this code print?
    let a = 47;
    let b = 35;
    console.log(a + b);
40. 40.⚡ What number does this code print?
    let a = 41;
    let b = 1;
    console.log(a + b);

Free html and css lessons, practice and worksheets at talentjr.in/html-css-for-kids