JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 821 · 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) let (b) give (c) make (d) put
2. 2.⚡ Which JavaScript word writes in the console? (a) alert() (b) console.log() (c) for (d) let
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "1";
   let y = 1;
   console.log(x + y); (a) Error (b) 11 (c) 2
4. 4.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <script> (c) <style> (d) <js>
5. 5.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .html (c) .jpg (d) .js
6. 6.⚡ What does this code print? (Look at the quotes!)
   let x = "3";
   let y = 9;
   console.log(x + y); (a) 12 (b) Error (c) 39
7. 7.⚡ What does JavaScript add to a web page? (a) the page title (b) actions and changes (c) the domain name (d) only colours
8. 8.⚡ What does this code print? (Look at the quotes!)
   let x = "4";
   let y = 1;
   console.log(x + y); (a) Error (b) 5 (c) 41
9. 9.⚡ What number does this code print?
   let a = 6;
   let b = 1;
   console.log(a + b);
10. 10.⚡ What number does this code print?
    let marks = 16;
    marks = marks + 19;
    marks = marks - 5;
    console.log(marks);
11. 11.⚡ What number does this code print?
    let a = 7;
    let b = 2;
    console.log(a * b);
12. 12.⚡ What number does this code print?
    let a = 30;
    let b = 14;
    console.log(a - b);
13. 13.⚡ Where does console.log() show its output? (a) in the address bar (b) in the console (c) on the title bar (d) on the printer
14. 14.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 1;
    console.log(x + y); (a) Error (b) 3 (c) 21
15. 15.⚡ Which JavaScript word shows a pop-up box? (a) let (b) for (c) if (d) alert()
16. 16.⚡ What number does this code print?
    let books = 10;
    books = books + 5;
    books = books - 1;
    console.log(books);
17. 17.⚡ What number does this code print?
    let books = 10;
    books = books + 2;
    books = books - 6;
    console.log(books);
18. 18.⚡ Which JavaScript word makes a new variable? (a) for (b) if (c) console.log() (d) let
19. 19.⚡ What does this code show?
    let name = "Kabir";
    alert("Hello, " + name + "!"); (a) Kabir (b) name (c) Hello, Kabir! (d) Hello, name!
20. 20.⚡ What number does this code print?
    let a = 39;
    let b = 12;
    console.log(a - b);
21. 21.⚡ Which JavaScript word runs code when true? (a) console.log() (b) let (c) if (d) alert()
22. 22.⚡ What number does this code print?
    let a = 32;
    let b = 6;
    console.log(a - b);
23. 23.⚡ What does alert() show? (a) a picture (b) a new tab (c) a table (d) a pop-up box
24. 24.⚡ What number does this code print?
    let marks = 14;
    marks = marks + 5;
    marks = marks - 12;
    console.log(marks);
25. 25.⚡ What number does this code print?
    let coins = 30;
    coins = coins + 11;
    coins = coins - 28;
    console.log(coins);
26. 26.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 4;
    console.log(x + y); (a) 14 (b) 5 (c) Error
27. 27.⚡ What number does this code print?
    let coins = 10;
    coins = coins + 12;
    coins = coins - 6;
    console.log(coins);
28. 28.⚡ What number does this code print?
    let books = 9;
    books = books + 3;
    books = books - 10;
    console.log(books);
29. 29.⚡ What number does this code print?
    let a = 28;
    let b = 19;
    console.log(a + b);
30. 30.⚡ Which JavaScript word repeats code? (a) alert() (b) for (c) if (d) let
31. 31.⚡ What does this code show?
    let name = "Kabir";
    console.log("Well done, " + name + "!"); (a) Kabir (b) Well done, Kabir! (c) name (d) Well done, name!
32. 32.⚡ What number does this code print?
    let a = 33;
    let b = 19;
    console.log(a - b);
33. 33.⚡ What number does this code print?
    let score = 14;
    score = score + 12;
    score = score - 15;
    console.log(score);
34. 34.⚡ What number does this code print?
    let runs = 18;
    runs = runs + 9;
    runs = runs - 8;
    console.log(runs);
35. 35.⚡ What number does this code print?
    let a = 4;
    let b = 6;
    console.log(a * b);
36. 36.⚡ What does this code show?
    let name = "Aman";
    alert("Well done, " + name + "!"); (a) name (b) Aman (c) Well done, name! (d) Well done, Aman!
37. 37.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 7;
    console.log(x + y); (a) Error (b) 15 (c) 87
38. 38.⚡ What number does this code print?
    let a = 8;
    let b = 4;
    console.log(a * b);
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 1;
    console.log(x + y); (a) 91 (b) Error (c) 10
40. 40.⚡ What number does this code print?
    let apples = 28;
    apples = apples + 18;
    apples = apples - 30;
    console.log(apples);

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