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JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 947 · 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.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 6;
    console.log(x + y);     (a) 16 (b) 7 (c) Error
  3. 3.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 8;
    console.log(x + y);     (a) 12 (b) Error (c) 48
  4. 4.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <style> (c) <script> (d) <js>
  5. 5.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .css (c) .html (d) .js
  6. 6.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 7;
    console.log(x + y);     (a) 47 (b) 11 (c) Error
  7. 7.⚡ Which JavaScript word shows a pop-up box? (a) let (b) for (c) console.log() (d) alert()
  8. 8.⚡ What does this code show?
    let name = "Arjun";
    alert("Welcome, " + name + "!");     (a) Arjun (b) Welcome, name! (c) Welcome, Arjun! (d) name
  9. 9.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 2;
    console.log(x + y);     (a) 22 (b) 4 (c) Error
  10. 10.⚡ Which JavaScript word repeats code? (a) let (b) console.log() (c) for (d) alert()
  11. 11.⚡ What number does this code print?
    let a = 16;
    let b = 12;
    console.log(a - b);
  12. 12.⚡ Which JavaScript word runs code when true? (a) for (b) if (c) alert() (d) console.log()
  13. 13.⚡ What does this code show?
    let name = "Arjun";
    alert("Well done, " + name + "!");     (a) Well done, Arjun! (b) name (c) Arjun (d) Well done, name!
  14. 14.⚡ What does this code show?
    let name = "Arjun";
    console.log("Welcome, " + name + "!");     (a) Arjun (b) Welcome, Arjun! (c) name (d) Welcome, name!
  15. 15.⚡ What does alert() show? (a) a pop-up box (b) a table (c) a new tab (d) a picture
  16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 6;
    console.log(x + y);     (a) Error (b) 56 (c) 11
  17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 5;
    console.log(x + y);     (a) 12 (b) 75 (c) Error
  18. 18.⚡ What does this code show?
    let name = "Arjun";
    console.log("Well done, " + name + "!");     (a) Well done, name! (b) name (c) Well done, Arjun! (d) Arjun
  19. 19.⚡ Where does console.log() show its output? (a) in the console (b) in the address bar (c) on the printer (d) on the title bar
  20. 20.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 2;
    console.log(x + y);     (a) 72 (b) Error (c) 9
  21. 21.⚡ What number does this code print?
    let a = 4;
    let b = 10;
    console.log(a * b);
  22. 22.⚡ Which JavaScript word writes in the console? (a) alert() (b) for (c) let (d) console.log()
  23. 23.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 2;
    console.log(x + y);     (a) 42 (b) Error (c) 6
  24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 5;
    console.log(x + y);     (a) 35 (b) 8 (c) Error
  25. 25.⚡ What number does this code print?
    let a = 23;
    let b = 16;
    console.log(a - b);
  26. 26.⚡ What number does this code print?
    let a = 48;
    let b = 9;
    console.log(a - b);
  27. 27.⚡ What does this code show?
    let name = "Meera";
    console.log("Welcome, " + name + "!");     (a) Meera (b) name (c) Welcome, Meera! (d) Welcome, name!
  28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 5;
    console.log(x + y);     (a) 9 (b) Error (c) 45
  29. 29.⚡ What number does this code print?
    let coins = 30;
    coins = coins + 6;
    coins = coins - 29;
    console.log(coins);
  30. 30.⚡ What does this code show?
    let name = "Riya";
    console.log("Hi, " + name + "!");     (a) Hi, name! (b) name (c) Riya (d) Hi, Riya!
  31. 31.⚡ Which JavaScript word makes a new variable? (a) console.log() (b) alert() (c) if (d) let
  32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 8;
    console.log(x + y);     (a) 28 (b) Error (c) 10
  33. 33.⚡ What does this code show?
    let name = "Riya";
    console.log("Well done, " + name + "!");     (a) Well done, Riya! (b) Riya (c) Well done, name! (d) name
  34. 34.⚡ What number does this code print?
    let a = 30;
    let b = 20;
    console.log(a - b);
  35. 35.⚡ What does JavaScript add to a web page? (a) the page title (b) only colours (c) the domain name (d) actions and changes
  36. 36.⚡ What number does this code print?
    let a = 11;
    let b = 8;
    console.log(a - b);
  37. 37.⚡ What does this code show?
    let name = "Meera";
    alert("Hello, " + name + "!");     (a) name (b) Hello, Meera! (c) Meera (d) Hello, name!
  38. 38.⚡ What does this code show?
    let name = "Meera";
    alert("Well done, " + name + "!");     (a) name (b) Well done, name! (c) Meera (d) Well done, Meera!
  39. 39.⚡ What number does this code print?
    let apples = 8;
    apples = apples + 5;
    apples = apples - 6;
    console.log(apples);
  40. 40.⚡ What number does this code print?
    let a = 11;
    let b = 3;
    console.log(a * b);

Answer key

  1. let
  2. 16
  3. 48
  4. <script>
  5. .js
  6. 47
  7. alert()
  8. Welcome, Arjun!
  9. 22
  10. for
  11. 4
  12. if
  13. Well done, Arjun!
  14. Welcome, Arjun!
  15. a pop-up box
  16. 56
  17. 75
  18. Well done, Arjun!
  19. in the console
  20. 72
  21. 40
  22. console.log()
  23. 42
  24. 35
  25. 7
  26. 39
  27. Welcome, Meera!
  28. 45
  29. 7
  30. Hi, Riya!
  31. let
  32. 28
  33. Well done, Riya!
  34. 10
  35. actions and changes
  36. 3
  37. Hello, Meera!
  38. Well done, Meera!
  39. 7
  40. 33

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