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JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 750 · 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 runs code when true? (a) let (b) alert() (c) for (d) if
  2. 2.⚡ What number does this code print?
    let a = 37;
    let b = 17;
    console.log(a - b);
  3. 3.⚡ What number does this code print?
    let runs = 29;
    runs = runs + 4;
    runs = runs - 13;
    console.log(runs);
  4. 4.⚡ What number does this code print?
    let marks = 23;
    marks = marks + 18;
    marks = marks - 22;
    console.log(marks);
  5. 5.⚡ Which JavaScript word makes a new variable? (a) console.log() (b) for (c) let (d) if
  6. 6.⚡ What does JavaScript add to a web page? (a) the domain name (b) only colours (c) the page title (d) actions and changes
  7. 7.⚡ What number does this code print?
    let a = 10;
    let b = 11;
    console.log(a * b);
  8. 8.⚡ What number does this code print?
    let score = 28;
    score = score + 5;
    score = score - 27;
    console.log(score);
  9. 9.⚡ What does this code show?
    let name = "Aman";
    console.log("Welcome, " + name + "!");     (a) name (b) Aman (c) Welcome, name! (d) Welcome, Aman!
  10. 10.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .jpg (c) .html (d) .css
  11. 11.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) for (c) if (d) alert()
  12. 12.⚡ Which JavaScript word writes in the console? (a) if (b) for (c) console.log() (d) let
  13. 13.⚡ What does alert() show? (a) a new tab (b) a table (c) a pop-up box (d) a picture
  14. 14.⚡ Which word makes a new variable? (a) give (b) let (c) make (d) put
  15. 15.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 3;
    console.log(x + y);     (a) 23 (b) 5 (c) Error
  16. 16.⚡ What number does this code print?
    let marks = 7;
    marks = marks + 13;
    marks = marks - 1;
    console.log(marks);
  17. 17.⚡ 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
  18. 18.⚡ What number does this code print?
    let a = 35;
    let b = 26;
    console.log(a - b);
  19. 19.⚡ 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
  20. 20.⚡ What number does this code print?
    let a = 12;
    let b = 1;
    console.log(a - b);
  21. 21.⚡ What number does this code print?
    let a = 45;
    let b = 5;
    console.log(a + b);
  22. 22.⚡ 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
  23. 23.⚡ What number does this code print?
    let a = 35;
    let b = 12;
    console.log(a - b);
  24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 5;
    console.log(x + y);     (a) Error (b) 6 (c) 15
  25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 5;
    console.log(x + y);     (a) 8 (b) Error (c) 35
  26. 26.⚡ What does this code show?
    let name = "Meera";
    console.log("Well done, " + name + "!");     (a) name (b) Meera (c) Well done, Meera! (d) Well done, name!
  27. 27.⚡ What number does this code print?
    let a = 2;
    let b = 3;
    console.log(a * b);
  28. 28.⚡ What number does this code print?
    let a = 32;
    let b = 11;
    console.log(a - b);
  29. 29.⚡ What number does this code print?
    let a = 4;
    let b = 2;
    console.log(a * b);
  30. 30.⚡ What number does this code print?
    let a = 4;
    let b = 11;
    console.log(a * b);
  31. 31.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 5;
    console.log(x + y);     (a) Error (b) 25 (c) 7
  32. 32.⚡ What does this code show?
    let name = "Kabir";
    alert("Well done, " + name + "!");     (a) Well done, name! (b) name (c) Kabir (d) Well done, Kabir!
  33. 33.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!");     (a) Kabir (b) Hello, name! (c) Hello, Kabir! (d) name
  34. 34.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 6;
    console.log(x + y);     (a) 16 (b) Error (c) 7
  35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 8;
    console.log(x + y);     (a) Error (b) 13 (c) 58
  36. 36.⚡ Which JavaScript word repeats code? (a) for (b) alert() (c) if (d) let
  37. 37.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!");     (a) Hello, Arjun! (b) name (c) Hello, name! (d) Arjun
  38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 1;
    console.log(x + y);     (a) 6 (b) 51 (c) Error
  39. 39.⚡ What does this code show?
    let name = "Kabir";
    alert("Hi, " + name + "!");     (a) name (b) Hi, name! (c) Hi, Kabir! (d) Kabir
  40. 40.⚡ What does this code show?
    let name = "Aman";
    alert("Well done, " + name + "!");     (a) Well done, Aman! (b) Well done, name! (c) Aman (d) name

Answer key

  1. if
  2. 20
  3. 20
  4. 19
  5. let
  6. actions and changes
  7. 110
  8. 6
  9. Welcome, Aman!
  10. .js
  11. alert()
  12. console.log()
  13. a pop-up box
  14. let
  15. 23
  16. 19
  17. 72
  18. 9
  19. 45
  20. 11
  21. 50
  22. in the console
  23. 23
  24. 15
  25. 35
  26. Well done, Meera!
  27. 6
  28. 21
  29. 8
  30. 44
  31. 25
  32. Well done, Kabir!
  33. Hello, Kabir!
  34. 16
  35. 58
  36. for
  37. Hello, Arjun!
  38. 51
  39. Hi, Kabir!
  40. Well done, Aman!

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