JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 34 · 40 questions

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".

1. 1.⚡ Which JavaScript word writes in the console? (a) if (b) alert() (c) for (d) console.log()
2. 2.⚡ What number does this code print?
   let a = 11;
   let b = 10;
   console.log(a * b);
3. 3.⚡ Which word makes a new variable? (a) give (b) let (c) make (d) put
4. 4.⚡ Which JavaScript word runs code when true? (a) for (b) let (c) alert() (d) if
5. 5.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .js (c) .jpg (d) .html
6. 6.⚡ What number does this code print?
   let score = 28;
   score = score + 10;
   score = score - 7;
   console.log(score);
7. 7.⚡ What does this code print? (Look at the quotes!)
   let x = "8";
   let y = 8;
   console.log(x + y); (a) Error (b) 88 (c) 16
8. 8.⚡ What does this code print? (Look at the quotes!)
   let x = "4";
   let y = 2;
   console.log(x + y); (a) Error (b) 6 (c) 42
9. 9.⚡ What does this code show?
   let name = "Meera";
   alert("Hi, " + name + "!"); (a) Meera (b) Hi, name! (c) Hi, Meera! (d) name
10. 10.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <style> (c) <script> (d) <js>
11. 11.⚡ What number does this code print?
    let a = 19;
    let b = 7;
    console.log(a - b);
12. 12.⚡ Which JavaScript word shows a pop-up box? (a) for (b) alert() (c) let (d) console.log()
13. 13.⚡ What number does this code print?
    let a = 19;
    let b = 6;
    console.log(a + b);
14. 14.⚡ Which JavaScript word makes a new variable? (a) alert() (b) if (c) console.log() (d) let
15. 15.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 5;
    console.log(x + y); (a) Error (b) 8 (c) 35
16. 16.⚡ What number does this code print?
    let books = 24;
    books = books + 7;
    books = books - 29;
    console.log(books);
17. 17.⚡ What does alert() show? (a) a new tab (b) a table (c) a picture (d) a pop-up box
18. 18.⚡ What does this code show?
    let name = "Kabir";
    alert("Hi, " + name + "!"); (a) name (b) Hi, Kabir! (c) Hi, name! (d) Kabir
19. 19.⚡ What does this code show?
    let name = "Kabir";
    alert("Welcome, " + name + "!"); (a) Kabir (b) Welcome, name! (c) name (d) Welcome, Kabir!
20. 20.⚡ What number does this code print?
    let a = 60;
    let b = 8;
    console.log(a + b);
21. 21.⚡ What does this code show?
    let name = "Kabir";
    console.log("Well done, " + name + "!"); (a) name (b) Kabir (c) Well done, name! (d) Well done, Kabir!
22. 22.⚡ What does this code show?
    let name = "Meera";
    console.log("Welcome, " + name + "!"); (a) name (b) Welcome, Meera! (c) Meera (d) Welcome, name!
23. 23.⚡ What number does this code print?
    let marks = 9;
    marks = marks + 5;
    marks = marks - 3;
    console.log(marks);
24. 24.⚡ What number does this code print?
    let score = 25;
    score = score + 9;
    score = score - 3;
    console.log(score);
25. 25.⚡ What number does this code print?
    let a = 36;
    let b = 17;
    console.log(a + b);
26. 26.⚡ What number does this code print?
    let a = 33;
    let b = 10;
    console.log(a - b);
27. 27.⚡ What does this code show?
    let name = "Arjun";
    alert("Well done, " + name + "!"); (a) Well done, name! (b) Well done, Arjun! (c) Arjun (d) name
28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 6;
    console.log(x + y); (a) 10 (b) 46 (c) Error
29. 29.⚡ What number does this code print?
    let a = 14;
    let b = 6;
    console.log(a - b);
30. 30.⚡ What does JavaScript add to a web page? (a) the page title (b) the domain name (c) only colours (d) actions and changes
31. 31.⚡ What does this code show?
    let name = "Arjun";
    alert("Welcome, " + name + "!"); (a) Arjun (b) name (c) Welcome, Arjun! (d) Welcome, name!
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 6;
    console.log(x + y); (a) 76 (b) 13 (c) Error
33. 33.⚡ Where does console.log() show its output? (a) in the address bar (b) on the printer (c) in the console (d) on the title bar
34. 34.⚡ What does this code show?
    let name = "Riya";
    console.log("Hi, " + name + "!"); (a) Riya (b) name (c) Hi, Riya! (d) Hi, name!
35. 35.⚡ What number does this code print?
    let a = 29;
    let b = 12;
    console.log(a + b);
36. 36.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 3;
    console.log(x + y); (a) 53 (b) Error (c) 8
37. 37.⚡ What number does this code print?
    let score = 17;
    score = score + 9;
    score = score - 14;
    console.log(score);
38. 38.⚡ What does this code show?
    let name = "Aman";
    console.log("Hi, " + name + "!"); (a) Hi, Aman! (b) name (c) Hi, name! (d) Aman
39. 39.⚡ What number does this code print?
    let a = 51;
    let b = 8;
    console.log(a + b);
40. 40.⚡ What number does this code print?
    let a = 10;
    let b = 7;
    console.log(a - b);

Free html and css lessons, practice and worksheets at talentjr.in/html-css-for-kids