JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 286 · 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 word makes a new variable? (a) give (b) make (c) put (d) let
2. 2.⚡ What number does this code print?
   let a = 8;
   let b = 5;
   console.log(a - b);
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "4";
   let y = 1;
   console.log(x + y); (a) 41 (b) Error (c) 5
4. 4.⚡ Which JavaScript word repeats code? (a) for (b) let (c) if (d) alert()
5. 5.⚡ What number does this code print?
   let apples = 7;
   apples = apples + 2;
   apples = apples - 8;
   console.log(apples);
6. 6.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) if (c) let (d) for
7. 7.⚡ Which JavaScript word makes a new variable? (a) for (b) alert() (c) let (d) console.log()
8. 8.⚡ What number does this code print?
   let marks = 8;
   marks = marks + 17;
   marks = marks - 19;
   console.log(marks);
9. 9.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .jpg (c) .css (d) .js
10. 10.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Hi, Kabir! (d) Kabir
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 1;
    console.log(x + y); (a) 3 (b) 21 (c) Error
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 6;
    console.log(x + y); (a) 76 (b) Error (c) 13
13. 13.⚡ What number does this code print?
    let books = 15;
    books = books + 11;
    books = books - 20;
    console.log(books);
14. 14.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 8;
    console.log(x + y); (a) 12 (b) 48 (c) Error
15. 15.⚡ What does this code show?
    let name = "Meera";
    console.log("Hi, " + name + "!"); (a) Hi, Meera! (b) Hi, name! (c) Meera (d) name
16. 16.⚡ What does this code show?
    let name = "Riya";
    console.log("Well done, " + name + "!"); (a) Riya (b) Well done, name! (c) Well done, Riya! (d) name
17. 17.⚡ What does this code show?
    let name = "Riya";
    console.log("Hi, " + name + "!"); (a) Riya (b) Hi, Riya! (c) name (d) Hi, name!
18. 18.⚡ Which JavaScript word runs code when true? (a) alert() (b) let (c) console.log() (d) if
19. 19.⚡ Which JavaScript word writes in the console? (a) console.log() (b) for (c) alert() (d) if
20. 20.⚡ What number does this code print?
    let a = 6;
    let b = 5;
    console.log(a * b);
21. 21.⚡ What number does this code print?
    let score = 5;
    score = score + 3;
    score = score - 1;
    console.log(score);
22. 22.⚡ What number does this code print?
    let a = 26;
    let b = 23;
    console.log(a - b);
23. 23.⚡ Where does console.log() show its output? (a) on the title bar (b) on the printer (c) in the address bar (d) in the console
24. 24.⚡ What number does this code print?
    let a = 25;
    let b = 3;
    console.log(a + b);
25. 25.⚡ What does JavaScript add to a web page? (a) the domain name (b) the page title (c) only colours (d) actions and changes
26. 26.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <style> (c) <script> (d) <code>
27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 2;
    console.log(x + y); (a) 82 (b) Error (c) 10
28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 9;
    console.log(x + y); (a) 10 (b) Error (c) 19
29. 29.⚡ What number does this code print?
    let marks = 11;
    marks = marks + 12;
    marks = marks - 14;
    console.log(marks);
30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 3;
    console.log(x + y); (a) Error (b) 11 (c) 83
31. 31.⚡ What number does this code print?
    let runs = 14;
    runs = runs + 7;
    runs = runs - 9;
    console.log(runs);
32. 32.⚡ What does this code show?
    let name = "Zoya";
    alert("Welcome, " + name + "!"); (a) Welcome, Zoya! (b) Zoya (c) name (d) Welcome, name!
33. 33.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 4;
    console.log(x + y); (a) Error (b) 84 (c) 12
34. 34.⚡ What number does this code print?
    let apples = 10;
    apples = apples + 16;
    apples = apples - 22;
    console.log(apples);
35. 35.⚡ What number does this code print?
    let books = 26;
    books = books + 8;
    books = books - 31;
    console.log(books);
36. 36.⚡ What does this code show?
    let name = "Arjun";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Arjun (d) Hi, Arjun!
37. 37.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) Riya (b) Hi, Riya! (c) name (d) Hi, name!
38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 7;
    console.log(x + y); (a) 57 (b) Error (c) 12
39. 39.⚡ What number does this code print?
    let runs = 20;
    runs = runs + 6;
    runs = runs - 11;
    console.log(runs);
40. 40.⚡ What number does this code print?
    let score = 25;
    score = score + 8;
    score = score - 5;
    console.log(score);

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