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JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 228 · 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 number does this code print?
    let a = 42;
    let b = 27;
    console.log(a - b);
  2. 2.⚡ Which JavaScript word runs code when true? (a) alert() (b) console.log() (c) if (d) for
  3. 3.⚡ What does JavaScript add to a web page? (a) actions and changes (b) only colours (c) the page title (d) the domain name
  4. 4.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!");     (a) Arjun (b) name (c) Hello, name! (d) Hello, Arjun!
  5. 5.⚡ What number does this code print?
    let marks = 25;
    marks = marks + 18;
    marks = marks - 32;
    console.log(marks);
  6. 6.⚡ Where does console.log() show its output? (a) on the title bar (b) in the console (c) in the address bar (d) on the printer
  7. 7.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <code> (c) <script> (d) <style>
  8. 8.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 6;
    console.log(x + y);     (a) 7 (b) Error (c) 16
  9. 9.⚡ What does alert() show? (a) a table (b) a pop-up box (c) a picture (d) a new tab
  10. 10.⚡ Which JavaScript word repeats code? (a) for (b) alert() (c) console.log() (d) if
  11. 11.⚡ Which JavaScript word shows a pop-up box? (a) for (b) console.log() (c) alert() (d) if
  12. 12.⚡ What number does this code print?
    let apples = 8;
    apples = apples + 4;
    apples = apples - 7;
    console.log(apples);
  13. 13.⚡ What does this code show?
    let name = "Aman";
    console.log("Hello, " + name + "!");     (a) name (b) Hello, name! (c) Aman (d) Hello, Aman!
  14. 14.⚡ Which JavaScript word makes a new variable? (a) let (b) if (c) for (d) console.log()
  15. 15.⚡ Which word makes a new variable? (a) let (b) make (c) put (d) give
  16. 16.⚡ What does this code show?
    let name = "Aman";
    console.log("Welcome, " + name + "!");     (a) name (b) Welcome, Aman! (c) Aman (d) Welcome, name!
  17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 9;
    console.log(x + y);     (a) 59 (b) 14 (c) Error
  18. 18.⚡ What number does this code print?
    let runs = 21;
    runs = runs + 2;
    runs = runs - 14;
    console.log(runs);
  19. 19.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 1;
    console.log(x + y);     (a) 3 (b) 21 (c) Error
  20. 20.⚡ What does this code show?
    let name = "Zoya";
    alert("Hello, " + name + "!");     (a) name (b) Hello, name! (c) Hello, Zoya! (d) Zoya
  21. 21.⚡ What number does this code print?
    let runs = 16;
    runs = runs + 17;
    runs = runs - 1;
    console.log(runs);
  22. 22.⚡ What does this code show?
    let name = "Aman";
    alert("Hi, " + name + "!");     (a) name (b) Hi, name! (c) Hi, Aman! (d) Aman
  23. 23.⚡ What does this code show?
    let name = "Kabir";
    alert("Hello, " + name + "!");     (a) name (b) Hello, name! (c) Hello, Kabir! (d) Kabir
  24. 24.⚡ Which JavaScript word writes in the console? (a) for (b) alert() (c) console.log() (d) let
  25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 1;
    console.log(x + y);     (a) 9 (b) Error (c) 81
  26. 26.⚡ What number does this code print?
    let a = 18;
    let b = 33;
    console.log(a + b);
  27. 27.⚡ What number does this code print?
    let a = 21;
    let b = 17;
    console.log(a + b);
  28. 28.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hi, " + name + "!");     (a) name (b) Zoya (c) Hi, Zoya! (d) Hi, name!
  29. 29.⚡ What does this code show?
    let name = "Aman";
    alert("Well done, " + name + "!");     (a) Well done, name! (b) name (c) Well done, Aman! (d) Aman
  30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 7;
    console.log(x + y);     (a) 77 (b) Error (c) 14
  31. 31.⚡ What number does this code print?
    let a = 42;
    let b = 27;
    console.log(a + b);
  32. 32.⚡ What number does this code print?
    let a = 51;
    let b = 38;
    console.log(a - b);
  33. 33.⚡ What number does this code print?
    let score = 8;
    score = score + 9;
    score = score - 7;
    console.log(score);
  34. 34.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .jpg (c) .js (d) .css
  35. 35.⚡ What number does this code print?
    let a = 6;
    let b = 8;
    console.log(a + b);
  36. 36.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 9;
    console.log(x + y);     (a) Error (b) 12 (c) 39
  37. 37.⚡ What does this code show?
    let name = "Meera";
    alert("Well done, " + name + "!");     (a) name (b) Meera (c) Well done, Meera! (d) Well done, name!
  38. 38.⚡ What does this code show?
    let name = "Riya";
    alert("Welcome, " + name + "!");     (a) Riya (b) name (c) Welcome, name! (d) Welcome, Riya!
  39. 39.⚡ What number does this code print?
    let a = 7;
    let b = 6;
    console.log(a * b);
  40. 40.⚡ What does this code show?
    let name = "Kabir";
    alert("Welcome, " + name + "!");     (a) Welcome, name! (b) name (c) Kabir (d) Welcome, Kabir!

Answer key

  1. 15
  2. if
  3. actions and changes
  4. Hello, Arjun!
  5. 11
  6. in the console
  7. <script>
  8. 16
  9. a pop-up box
  10. for
  11. alert()
  12. 5
  13. Hello, Aman!
  14. let
  15. let
  16. Welcome, Aman!
  17. 59
  18. 9
  19. 21
  20. Hello, Zoya!
  21. 32
  22. Hi, Aman!
  23. Hello, Kabir!
  24. console.log()
  25. 81
  26. 51
  27. 38
  28. Hi, Zoya!
  29. Well done, Aman!
  30. 77
  31. 69
  32. 13
  33. 10
  34. .js
  35. 14
  36. 39
  37. Well done, Meera!
  38. Welcome, Riya!
  39. 42
  40. Welcome, Kabir!

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