← JavaScript basics lesson New set →

JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 324 · 40 questions
TalentJR

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".

NameDateTime takenScore ___ / 40
  1. 1.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .css (c) .html (d) .js
  2. 2.⚡ Which JavaScript word makes a new variable? (a) let (b) alert() (c) console.log() (d) for
  3. 3.⚡ Where does console.log() show its output? (a) in the address bar (b) on the printer (c) on the title bar (d) in the console
  4. 4.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 7;
    console.log(x + y);     (a) 17 (b) Error (c) 8
  5. 5.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 9;
    console.log(x + y);     (a) Error (b) 59 (c) 14
  6. 6.⚡ What number does this code print?
    let marks = 12;
    marks = marks + 2;
    marks = marks - 10;
    console.log(marks);
  7. 7.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!");     (a) name (b) Kabir (c) Hello, Kabir! (d) Hello, name!
  8. 8.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!");     (a) Riya (b) Hi, Riya! (c) Hi, name! (d) name
  9. 9.⚡ What does this code show?
    let name = "Meera";
    console.log("Well done, " + name + "!");     (a) Meera (b) Well done, Meera! (c) Well done, name! (d) name
  10. 10.⚡ What does this code show?
    let name = "Riya";
    alert("Well done, " + name + "!");     (a) Well done, name! (b) Riya (c) name (d) Well done, Riya!
  11. 11.⚡ Which JavaScript word shows a pop-up box? (a) if (b) for (c) alert() (d) console.log()
  12. 12.⚡ What number does this code print?
    let marks = 7;
    marks = marks + 4;
    marks = marks - 5;
    console.log(marks);
  13. 13.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hello, " + name + "!");     (a) name (b) Zoya (c) Hello, Zoya! (d) Hello, name!
  14. 14.⚡ Which JavaScript word runs code when true? (a) if (b) alert() (c) for (d) console.log()
  15. 15.⚡ What does alert() show? (a) a new tab (b) a picture (c) a pop-up box (d) a table
  16. 16.⚡ What number does this code print?
    let a = 35;
    let b = 3;
    console.log(a + b);
  17. 17.⚡ What number does this code print?
    let coins = 6;
    coins = coins + 7;
    coins = coins - 1;
    console.log(coins);
  18. 18.⚡ What does this code show?
    let name = "Arjun";
    console.log("Welcome, " + name + "!");     (a) Arjun (b) Welcome, Arjun! (c) name (d) Welcome, name!
  19. 19.⚡ Which word makes a new variable? (a) give (b) put (c) make (d) let
  20. 20.⚡ What does this code show?
    let name = "Aman";
    alert("Well done, " + name + "!");     (a) Well done, Aman! (b) Aman (c) Well done, name! (d) name
  21. 21.⚡ What number does this code print?
    let marks = 29;
    marks = marks + 14;
    marks = marks - 12;
    console.log(marks);
  22. 22.⚡ What number does this code print?
    let a = 12;
    let b = 2;
    console.log(a + b);
  23. 23.⚡ What number does this code print?
    let score = 25;
    score = score + 13;
    score = score - 1;
    console.log(score);
  24. 24.⚡ What number does this code print?
    let books = 24;
    books = books + 11;
    books = books - 19;
    console.log(books);
  25. 25.⚡ What number does this code print?
    let score = 23;
    score = score + 11;
    score = score - 21;
    console.log(score);
  26. 26.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <code> (c) <script> (d) <js>
  27. 27.⚡ What number does this code print?
    let a = 44;
    let b = 26;
    console.log(a + b);
  28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 4;
    console.log(x + y);     (a) Error (b) 94 (c) 13
  29. 29.⚡ What number does this code print?
    let a = 6;
    let b = 12;
    console.log(a * b);
  30. 30.⚡ Which JavaScript word repeats code? (a) console.log() (b) let (c) for (d) alert()
  31. 31.⚡ Which JavaScript word writes in the console? (a) for (b) console.log() (c) if (d) alert()
  32. 32.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hi, " + name + "!");     (a) Kabir (b) Hi, name! (c) name (d) Hi, Kabir!
  33. 33.⚡ What number does this code print?
    let a = 26;
    let b = 9;
    console.log(a - b);
  34. 34.⚡ What number does this code print?
    let a = 37;
    let b = 1;
    console.log(a + b);
  35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 3;
    console.log(x + y);     (a) 43 (b) 7 (c) Error
  36. 36.⚡ What does JavaScript add to a web page? (a) the domain name (b) only colours (c) actions and changes (d) the page title
  37. 37.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!");     (a) Hello, Arjun! (b) Hello, name! (c) name (d) Arjun
  38. 38.⚡ What number does this code print?
    let a = 49;
    let b = 38;
    console.log(a - b);
  39. 39.⚡ What number does this code print?
    let score = 29;
    score = score + 19;
    score = score - 42;
    console.log(score);
  40. 40.⚡ What number does this code print?
    let coins = 9;
    coins = coins + 3;
    coins = coins - 11;
    console.log(coins);

Answer key

  1. .js
  2. let
  3. in the console
  4. 17
  5. 59
  6. 4
  7. Hello, Kabir!
  8. Hi, Riya!
  9. Well done, Meera!
  10. Well done, Riya!
  11. alert()
  12. 6
  13. Hello, Zoya!
  14. if
  15. a pop-up box
  16. 38
  17. 12
  18. Welcome, Arjun!
  19. let
  20. Well done, Aman!
  21. 31
  22. 14
  23. 37
  24. 16
  25. 13
  26. <script>
  27. 70
  28. 94
  29. 72
  30. for
  31. console.log()
  32. Hi, Kabir!
  33. 17
  34. 38
  35. 43
  36. actions and changes
  37. Hello, Arjun!
  38. 11
  39. 6
  40. 1

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