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JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 45 · 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.⚡ What does alert() show? (a) a picture (b) a pop-up box (c) a new tab (d) a table
  2. 2.⚡ What number does this code print?
    let a = 5;
    let b = 5;
    console.log(a * b);
  3. 3.⚡ What number does this code print?
    let marks = 18;
    marks = marks + 19;
    marks = marks - 21;
    console.log(marks);
  4. 4.⚡ What number does this code print?
    let books = 15;
    books = books + 15;
    books = books - 9;
    console.log(books);
  5. 5.⚡ What number does this code print?
    let a = 31;
    let b = 23;
    console.log(a + b);
  6. 6.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) if (c) let (d) console.log()
  7. 7.⚡ What does this code show?
    let name = "Riya";
    console.log("Hello, " + name + "!");     (a) Hello, name! (b) Riya (c) name (d) Hello, Riya!
  8. 8.⚡ What number does this code print?
    let a = 22;
    let b = 39;
    console.log(a + b);
  9. 9.⚡ Which word makes a new variable? (a) make (b) let (c) put (d) give
  10. 10.⚡ What number does this code print?
    let runs = 12;
    runs = runs + 17;
    runs = runs - 23;
    console.log(runs);
  11. 11.⚡ Which JavaScript word makes a new variable? (a) let (b) console.log() (c) alert() (d) for
  12. 12.⚡ Where does console.log() show its output? (a) in the console (b) in the address bar (c) on the title bar (d) on the printer
  13. 13.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 8;
    console.log(x + y);     (a) 14 (b) Error (c) 68
  14. 14.⚡ What number does this code print?
    let a = 23;
    let b = 9;
    console.log(a - b);
  15. 15.⚡ Which JavaScript word writes in the console? (a) let (b) alert() (c) console.log() (d) if
  16. 16.⚡ What number does this code print?
    let score = 30;
    score = score + 14;
    score = score - 34;
    console.log(score);
  17. 17.⚡ Which JavaScript word runs code when true? (a) for (b) alert() (c) if (d) console.log()
  18. 18.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!");     (a) name (b) Riya (c) Hello, Riya! (d) Hello, name!
  19. 19.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 1;
    console.log(x + y);     (a) Error (b) 61 (c) 7
  20. 20.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 6;
    console.log(x + y);     (a) Error (b) 9 (c) 36
  21. 21.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 6;
    console.log(x + y);     (a) 10 (b) Error (c) 46
  22. 22.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 5;
    console.log(x + y);     (a) Error (b) 95 (c) 14
  23. 23.⚡ What does this code show?
    let name = "Aman";
    console.log("Welcome, " + name + "!");     (a) Aman (b) Welcome, name! (c) Welcome, Aman! (d) name
  24. 24.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <script> (c) <code> (d) <style>
  25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 7;
    console.log(x + y);     (a) Error (b) 15 (c) 87
  26. 26.⚡ What number does this code print?
    let a = 41;
    let b = 30;
    console.log(a - b);
  27. 27.⚡ What number does this code print?
    let a = 18;
    let b = 6;
    console.log(a - b);
  28. 28.⚡ What number does this code print?
    let apples = 29;
    apples = apples + 17;
    apples = apples - 36;
    console.log(apples);
  29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 2;
    console.log(x + y);     (a) 52 (b) Error (c) 7
  30. 30.⚡ What number does this code print?
    let a = 8;
    let b = 11;
    console.log(a * b);
  31. 31.⚡ What number does this code print?
    let marks = 11;
    marks = marks + 19;
    marks = marks - 25;
    console.log(marks);
  32. 32.⚡ What does this code show?
    let name = "Aman";
    alert("Well done, " + name + "!");     (a) Aman (b) Well done, name! (c) Well done, Aman! (d) name
  33. 33.⚡ What does this code show?
    let name = "Riya";
    alert("Welcome, " + name + "!");     (a) Welcome, name! (b) Welcome, Riya! (c) name (d) Riya
  34. 34.⚡ What number does this code print?
    let a = 56;
    let b = 13;
    console.log(a - b);
  35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 3;
    console.log(x + y);     (a) Error (b) 83 (c) 11
  36. 36.⚡ What does this code show?
    let name = "Aman";
    alert("Hello, " + name + "!");     (a) Hello, name! (b) Hello, Aman! (c) Aman (d) name
  37. 37.⚡ What number does this code print?
    let score = 25;
    score = score + 9;
    score = score - 2;
    console.log(score);
  38. 38.⚡ What does this code show?
    let name = "Aman";
    console.log("Hi, " + name + "!");     (a) Aman (b) Hi, name! (c) Hi, Aman! (d) name
  39. 39.⚡ What does JavaScript add to a web page? (a) the domain name (b) the page title (c) only colours (d) actions and changes
  40. 40.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .jpg (c) .html (d) .js

Answer key

  1. a pop-up box
  2. 25
  3. 16
  4. 21
  5. 54
  6. alert()
  7. Hello, Riya!
  8. 61
  9. let
  10. 6
  11. let
  12. in the console
  13. 68
  14. 14
  15. console.log()
  16. 10
  17. if
  18. Hello, Riya!
  19. 61
  20. 36
  21. 46
  22. 95
  23. Welcome, Aman!
  24. <script>
  25. 87
  26. 11
  27. 12
  28. 10
  29. 52
  30. 88
  31. 5
  32. Well done, Aman!
  33. Welcome, Riya!
  34. 43
  35. 83
  36. Hello, Aman!
  37. 32
  38. Hi, Aman!
  39. actions and changes
  40. .js

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