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JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 287 · 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.⚡ Which JavaScript word makes a new variable? (a) let (b) if (c) for (d) alert()
  2. 2.⚡ What number does this code print?
    let a = 9;
    let b = 2;
    console.log(a - b);
  3. 3.⚡ What does alert() show? (a) a picture (b) a pop-up box (c) a table (d) a new tab
  4. 4.⚡ What does this code show?
    let name = "Aman";
    alert("Hello, " + name + "!");     (a) Hello, name! (b) name (c) Aman (d) Hello, Aman!
  5. 5.⚡ What number does this code print?
    let a = 42;
    let b = 6;
    console.log(a + b);
  6. 6.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .html (c) .js (d) .jpg
  7. 7.⚡ Which JavaScript word writes in the console? (a) if (b) console.log() (c) alert() (d) let
  8. 8.⚡ What number does this code print?
    let a = 37;
    let b = 20;
    console.log(a - b);
  9. 9.⚡ What number does this code print?
    let a = 21;
    let b = 33;
    console.log(a + b);
  10. 10.⚡ What number does this code print?
    let a = 40;
    let b = 9;
    console.log(a + b);
  11. 11.⚡ What number does this code print?
    let a = 44;
    let b = 36;
    console.log(a + b);
  12. 12.⚡ Which JavaScript word repeats code? (a) let (b) for (c) console.log() (d) alert()
  13. 13.⚡ What number does this code print?
    let books = 17;
    books = books + 14;
    books = books - 17;
    console.log(books);
  14. 14.⚡ What number does this code print?
    let a = 7;
    let b = 23;
    console.log(a + b);
  15. 15.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hello, " + name + "!");     (a) name (b) Hello, name! (c) Arjun (d) Hello, Arjun!
  16. 16.⚡ What does this code show?
    let name = "Kabir";
    alert("Hello, " + name + "!");     (a) Kabir (b) Hello, name! (c) Hello, Kabir! (d) name
  17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 7;
    console.log(x + y);     (a) Error (b) 47 (c) 11
  18. 18.⚡ What does this code show?
    let name = "Riya";
    alert("Well done, " + name + "!");     (a) Riya (b) name (c) Well done, name! (d) Well done, Riya!
  19. 19.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hello, " + name + "!");     (a) Zoya (b) name (c) Hello, name! (d) Hello, Zoya!
  20. 20.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <js> (c) <code> (d) <script>
  21. 21.⚡ What does this code show?
    let name = "Zoya";
    alert("Well done, " + name + "!");     (a) Zoya (b) Well done, Zoya! (c) Well done, name! (d) name
  22. 22.⚡ What number does this code print?
    let a = 20;
    let b = 12;
    console.log(a - b);
  23. 23.⚡ What number does this code print?
    let a = 8;
    let b = 1;
    console.log(a + b);
  24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 2;
    console.log(x + y);     (a) 12 (b) 3 (c) Error
  25. 25.⚡ Which JavaScript word runs code when true? (a) console.log() (b) alert() (c) if (d) for
  26. 26.⚡ What number does this code print?
    let a = 13;
    let b = 19;
    console.log(a + b);
  27. 27.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) let (c) console.log() (d) for
  28. 28.⚡ What number does this code print?
    let coins = 9;
    coins = coins + 15;
    coins = coins - 2;
    console.log(coins);
  29. 29.⚡ What does JavaScript add to a web page? (a) the page title (b) actions and changes (c) only colours (d) the domain name
  30. 30.⚡ What does this code show?
    let name = "Kabir";
    alert("Welcome, " + name + "!");     (a) Welcome, Kabir! (b) Welcome, name! (c) Kabir (d) name
  31. 31.⚡ What does this code show?
    let name = "Meera";
    console.log("Hi, " + name + "!");     (a) Hi, name! (b) Meera (c) name (d) Hi, Meera!
  32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 9;
    console.log(x + y);     (a) 11 (b) Error (c) 29
  33. 33.⚡ 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
  34. 34.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 7;
    console.log(x + y);     (a) 10 (b) Error (c) 37
  35. 35.⚡ What does this code show?
    let name = "Riya";
    console.log("Hello, " + name + "!");     (a) Hello, name! (b) name (c) Hello, Riya! (d) Riya
  36. 36.⚡ What number does this code print?
    let a = 45;
    let b = 4;
    console.log(a + b);
  37. 37.⚡ What does this code show?
    let name = "Meera";
    alert("Hello, " + name + "!");     (a) name (b) Hello, name! (c) Hello, Meera! (d) Meera
  38. 38.⚡ What number does this code print?
    let runs = 29;
    runs = runs + 20;
    runs = runs - 20;
    console.log(runs);
  39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 1;
    console.log(x + y);     (a) 11 (b) Error (c) 2
  40. 40.⚡ What number does this code print?
    let score = 8;
    score = score + 2;
    score = score - 10;
    console.log(score);

Answer key

  1. let
  2. 7
  3. a pop-up box
  4. Hello, Aman!
  5. 48
  6. .js
  7. console.log()
  8. 17
  9. 54
  10. 49
  11. 80
  12. for
  13. 14
  14. 30
  15. Hello, Arjun!
  16. Hello, Kabir!
  17. 47
  18. Well done, Riya!
  19. Hello, Zoya!
  20. <script>
  21. Well done, Zoya!
  22. 8
  23. 9
  24. 12
  25. if
  26. 32
  27. alert()
  28. 22
  29. actions and changes
  30. Welcome, Kabir!
  31. Hi, Meera!
  32. 29
  33. in the console
  34. 37
  35. Hello, Riya!
  36. 49
  37. Hello, Meera!
  38. 29
  39. 11
  40. 0

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