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JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 619 · 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) for (b) console.log() (c) alert() (d) let
  2. 2.⚡ Which word makes a new variable? (a) let (b) give (c) put (d) make
  3. 3.⚡ What number does this code print?
    let a = 8;
    let b = 1;
    console.log(a - b);
  4. 4.⚡ What number does this code print?
    let a = 56;
    let b = 20;
    console.log(a + b);
  5. 5.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 8;
    console.log(x + y);     (a) 88 (b) 16 (c) Error
  6. 6.⚡ 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
  7. 7.⚡ What number does this code print?
    let a = 37;
    let b = 8;
    console.log(a + b);
  8. 8.⚡ What does JavaScript add to a web page? (a) the domain name (b) only colours (c) the page title (d) actions and changes
  9. 9.⚡ Which JavaScript word writes in the console? (a) let (b) console.log() (c) alert() (d) if
  10. 10.⚡ What number does this code print?
    let a = 35;
    let b = 33;
    console.log(a - b);
  11. 11.⚡ Which JavaScript word shows a pop-up box? (a) if (b) alert() (c) console.log() (d) let
  12. 12.⚡ What does this code show?
    let name = "Riya";
    console.log("Hello, " + name + "!");     (a) Hello, name! (b) Riya (c) Hello, Riya! (d) name
  13. 13.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .css (c) .html (d) .js
  14. 14.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 6;
    console.log(x + y);     (a) 7 (b) 16 (c) Error
  15. 15.⚡ What number does this code print?
    let apples = 20;
    apples = apples + 17;
    apples = apples - 1;
    console.log(apples);
  16. 16.⚡ What number does this code print?
    let a = 14;
    let b = 2;
    console.log(a - b);
  17. 17.⚡ What number does this code print?
    let a = 29;
    let b = 10;
    console.log(a - b);
  18. 18.⚡ What number does this code print?
    let books = 18;
    books = books + 11;
    books = books - 10;
    console.log(books);
  19. 19.⚡ What number does this code print?
    let a = 30;
    let b = 11;
    console.log(a - b);
  20. 20.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 4;
    console.log(x + y);     (a) Error (b) 10 (c) 64
  21. 21.⚡ What number does this code print?
    let a = 51;
    let b = 21;
    console.log(a + b);
  22. 22.⚡ What does alert() show? (a) a pop-up box (b) a picture (c) a table (d) a new tab
  23. 23.⚡ What number does this code print?
    let score = 5;
    score = score + 9;
    score = score - 12;
    console.log(score);
  24. 24.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!");     (a) Riya (b) Hello, Riya! (c) name (d) Hello, name!
  25. 25.⚡ Which JavaScript word runs code when true? (a) for (b) let (c) console.log() (d) if
  26. 26.⚡ What does this code show?
    let name = "Kabir";
    console.log("Welcome, " + name + "!");     (a) Kabir (b) Welcome, Kabir! (c) name (d) Welcome, name!
  27. 27.⚡ What number does this code print?
    let a = 19;
    let b = 8;
    console.log(a - b);
  28. 28.⚡ Which JavaScript word repeats code? (a) if (b) let (c) alert() (d) for
  29. 29.⚡ What number does this code print?
    let apples = 6;
    apples = apples + 2;
    apples = apples - 6;
    console.log(apples);
  30. 30.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hi, " + name + "!");     (a) name (b) Hi, Kabir! (c) Hi, name! (d) Kabir
  31. 31.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!");     (a) name (b) Hello, name! (c) Kabir (d) Hello, Kabir!
  32. 32.⚡ What number does this code print?
    let coins = 16;
    coins = coins + 7;
    coins = coins - 10;
    console.log(coins);
  33. 33.⚡ What number does this code print?
    let a = 43;
    let b = 4;
    console.log(a - b);
  34. 34.⚡ What number does this code print?
    let a = 36;
    let b = 38;
    console.log(a + b);
  35. 35.⚡ What does this code show?
    let name = "Kabir";
    alert("Hello, " + name + "!");     (a) name (b) Hello, name! (c) Hello, Kabir! (d) Kabir
  36. 36.⚡ 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
  37. 37.⚡ What does this code show?
    let name = "Aman";
    console.log("Well done, " + name + "!");     (a) Well done, name! (b) Aman (c) name (d) Well done, Aman!
  38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 9;
    console.log(x + y);     (a) 99 (b) 18 (c) Error
  39. 39.⚡ 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
  40. 40.⚡ 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

Answer key

  1. let
  2. let
  3. 7
  4. 76
  5. 88
  6. in the console
  7. 45
  8. actions and changes
  9. console.log()
  10. 2
  11. alert()
  12. Hello, Riya!
  13. .js
  14. 16
  15. 36
  16. 12
  17. 19
  18. 19
  19. 19
  20. 64
  21. 72
  22. a pop-up box
  23. 2
  24. Hello, Riya!
  25. if
  26. Welcome, Kabir!
  27. 11
  28. for
  29. 2
  30. Hi, Kabir!
  31. Hello, Kabir!
  32. 13
  33. 39
  34. 74
  35. Hello, Kabir!
  36. 77
  37. Well done, Aman!
  38. 99
  39. 39
  40. 68

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