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JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 19 · 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 word makes a new variable? (a) make (b) let (c) give (d) put
  2. 2.⚡ Which JavaScript word runs code when true? (a) if (b) alert() (c) for (d) let
  3. 3.⚡ Which JavaScript word writes in the console? (a) for (b) alert() (c) console.log() (d) let
  4. 4.⚡ Which JavaScript word repeats code? (a) if (b) console.log() (c) for (d) alert()
  5. 5.⚡ What number does this code print?
    let a = 47;
    let b = 4;
    console.log(a - b);
  6. 6.⚡ What number does this code print?
    let runs = 11;
    runs = runs + 15;
    runs = runs - 7;
    console.log(runs);
  7. 7.⚡ 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
  8. 8.⚡ What number does this code print?
    let apples = 23;
    apples = apples + 13;
    apples = apples - 8;
    console.log(apples);
  9. 9.⚡ What number does this code print?
    let a = 7;
    let b = 2;
    console.log(a * b);
  10. 10.⚡ Which JavaScript word makes a new variable? (a) console.log() (b) let (c) if (d) alert()
  11. 11.⚡ What does this code show?
    let name = "Zoya";
    alert("Well done, " + name + "!");     (a) Well done, name! (b) name (c) Zoya (d) Well done, Zoya!
  12. 12.⚡ What number does this code print?
    let a = 35;
    let b = 24;
    console.log(a - b);
  13. 13.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 4;
    console.log(x + y);     (a) 94 (b) 13 (c) Error
  14. 14.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <script> (c) <style> (d) <js>
  15. 15.⚡ What number does this code print?
    let a = 10;
    let b = 4;
    console.log(a * b);
  16. 16.⚡ What does this code show?
    let name = "Kabir";
    console.log("Well done, " + name + "!");     (a) Kabir (b) Well done, name! (c) Well done, Kabir! (d) name
  17. 17.⚡ What number does this code print?
    let a = 8;
    let b = 4;
    console.log(a * b);
  18. 18.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 2;
    console.log(x + y);     (a) 6 (b) 42 (c) Error
  19. 19.⚡ What number does this code print?
    let apples = 20;
    apples = apples + 20;
    apples = apples - 24;
    console.log(apples);
  20. 20.⚡ What number does this code print?
    let books = 25;
    books = books + 10;
    books = books - 21;
    console.log(books);
  21. 21.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) for (c) let (d) alert()
  22. 22.⚡ What does this code show?
    let name = "Kabir";
    console.log("Welcome, " + name + "!");     (a) name (b) Welcome, name! (c) Kabir (d) Welcome, Kabir!
  23. 23.⚡ What number does this code print?
    let a = 12;
    let b = 9;
    console.log(a * b);
  24. 24.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .jpg (c) .js (d) .html
  25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 5;
    console.log(x + y);     (a) Error (b) 7 (c) 25
  26. 26.⚡ What number does this code print?
    let a = 6;
    let b = 26;
    console.log(a + b);
  27. 27.⚡ What number does this code print?
    let coins = 23;
    coins = coins + 7;
    coins = coins - 27;
    console.log(coins);
  28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 2;
    console.log(x + y);     (a) 10 (b) 82 (c) Error
  29. 29.⚡ What number does this code print?
    let a = 55;
    let b = 31;
    console.log(a - b);
  30. 30.⚡ What does JavaScript add to a web page? (a) the domain name (b) only colours (c) actions and changes (d) the page title
  31. 31.⚡ What does this code show?
    let name = "Kabir";
    alert("Well done, " + name + "!");     (a) name (b) Well done, name! (c) Well done, Kabir! (d) Kabir
  32. 32.⚡ What does alert() show? (a) a new tab (b) a table (c) a pop-up box (d) a picture
  33. 33.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 4;
    console.log(x + y);     (a) 7 (b) 34 (c) Error
  34. 34.⚡ What number does this code print?
    let apples = 29;
    apples = apples + 17;
    apples = apples - 41;
    console.log(apples);
  35. 35.⚡ What number does this code print?
    let runs = 18;
    runs = runs + 7;
    runs = runs - 11;
    console.log(runs);
  36. 36.⚡ What number does this code print?
    let a = 18;
    let b = 12;
    console.log(a - b);
  37. 37.⚡ What number does this code print?
    let coins = 10;
    coins = coins + 14;
    coins = coins - 23;
    console.log(coins);
  38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 9;
    console.log(x + y);     (a) 29 (b) Error (c) 11
  39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 4;
    console.log(x + y);     (a) Error (b) 74 (c) 11
  40. 40.⚡ What number does this code print?
    let a = 58;
    let b = 6;
    console.log(a + b);

Answer key

  1. let
  2. if
  3. console.log()
  4. for
  5. 43
  6. 19
  7. in the console
  8. 28
  9. 14
  10. let
  11. Well done, Zoya!
  12. 11
  13. 94
  14. <script>
  15. 40
  16. Well done, Kabir!
  17. 32
  18. 42
  19. 16
  20. 14
  21. alert()
  22. Welcome, Kabir!
  23. 108
  24. .js
  25. 25
  26. 32
  27. 3
  28. 82
  29. 24
  30. actions and changes
  31. Well done, Kabir!
  32. a pop-up box
  33. 34
  34. 5
  35. 14
  36. 6
  37. 1
  38. 29
  39. 74
  40. 64

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