JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 478 · 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.⚡ What number does this code print?
   let a = 29;
   let b = 25;
   console.log(a - b);
2. 2.⚡ What number does this code print?
   let a = 12;
   let b = 16;
   console.log(a + b);
3. 3.⚡ What does this code show?
   let name = "Aman";
   console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) Aman (c) name (d) Welcome, Aman!
4. 4.⚡ What does JavaScript add to a web page? (a) the page title (b) only colours (c) actions and changes (d) the domain name
5. 5.⚡ Which JavaScript word writes in the console? (a) console.log() (b) let (c) for (d) alert()
6. 6.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .jpg (c) .html (d) .js
7. 7.⚡ What number does this code print?
   let a = 2;
   let b = 5;
   console.log(a * b);
8. 8.⚡ What does this code show?
   let name = "Aman";
   alert("Hi, " + name + "!"); (a) name (b) Hi, Aman! (c) Hi, name! (d) Aman
9. 9.⚡ Which JavaScript word shows a pop-up box? (a) if (b) console.log() (c) alert() (d) for
10. 10.⚡ What number does this code print?
    let score = 7;
    score = score + 6;
    score = score - 3;
    console.log(score);
11. 11.⚡ What number does this code print?
    let a = 8;
    let b = 8;
    console.log(a * b);
12. 12.⚡ What number does this code print?
    let coins = 29;
    coins = coins + 7;
    coins = coins - 8;
    console.log(coins);
13. 13.⚡ What number does this code print?
    let a = 55;
    let b = 5;
    console.log(a - b);
14. 14.⚡ What does alert() show? (a) a pop-up box (b) a picture (c) a new tab (d) a table
15. 15.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 1;
    console.log(x + y); (a) 81 (b) 9 (c) Error
16. 16.⚡ What number does this code print?
    let score = 25;
    score = score + 14;
    score = score - 6;
    console.log(score);
17. 17.⚡ What number does this code print?
    let a = 12;
    let b = 4;
    console.log(a * b);
18. 18.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hi, " + name + "!"); (a) Hi, Kabir! (b) Kabir (c) Hi, name! (d) name
19. 19.⚡ What does this code show?
    let name = "Aman";
    alert("Well done, " + name + "!"); (a) name (b) Well done, Aman! (c) Aman (d) Well done, name!
20. 20.⚡ 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
21. 21.⚡ Which word makes a new variable? (a) put (b) let (c) give (d) make
22. 22.⚡ Which JavaScript word makes a new variable? (a) for (b) let (c) if (d) alert()
23. 23.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 8;
    console.log(x + y); (a) Error (b) 68 (c) 14
24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 8;
    console.log(x + y); (a) Error (b) 18 (c) 9
25. 25.⚡ What does this code show?
    let name = "Riya";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) Riya (c) name (d) Well done, Riya!
26. 26.⚡ What number does this code print?
    let a = 10;
    let b = 3;
    console.log(a * b);
27. 27.⚡ What number does this code print?
    let a = 38;
    let b = 10;
    console.log(a + b);
28. 28.⚡ What number does this code print?
    let a = 38;
    let b = 8;
    console.log(a - b);
29. 29.⚡ What does this code show?
    let name = "Kabir";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) name (c) Well done, Kabir! (d) Kabir
30. 30.⚡ What number does this code print?
    let a = 33;
    let b = 7;
    console.log(a + b);
31. 31.⚡ Which JavaScript word repeats code? (a) if (b) alert() (c) for (d) console.log()
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 3;
    console.log(x + y); (a) 8 (b) 53 (c) Error
33. 33.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 7;
    console.log(x + y); (a) 16 (b) 97 (c) Error
34. 34.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <script> (c) <code> (d) <style>
35. 35.⚡ What number does this code print?
    let a = 29;
    let b = 27;
    console.log(a - b);
36. 36.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 2;
    console.log(x + y); (a) Error (b) 12 (c) 3
37. 37.⚡ What does this code show?
    let name = "Meera";
    console.log("Welcome, " + name + "!"); (a) name (b) Meera (c) Welcome, Meera! (d) Welcome, name!
38. 38.⚡ What number does this code print?
    let score = 30;
    score = score + 14;
    score = score - 17;
    console.log(score);
39. 39.⚡ Which JavaScript word runs code when true? (a) console.log() (b) alert() (c) if (d) let
40. 40.⚡ What number does this code print?
    let coins = 24;
    coins = coins + 11;
    coins = coins - 3;
    console.log(coins);

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