JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 727 · 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.⚡ Where does console.log() show its output? (a) on the title bar (b) on the printer (c) in the console (d) in the address bar
2. 2.⚡ What does this code print? (Look at the quotes!)
   let x = "8";
   let y = 9;
   console.log(x + y); (a) 17 (b) 89 (c) Error
3. 3.⚡ What number does this code print?
   let a = 33;
   let b = 31;
   console.log(a - b);
4. 4.⚡ Which JavaScript word writes in the console? (a) for (b) let (c) console.log() (d) if
5. 5.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <code> (c) <style> (d) <js>
6. 6.⚡ Which word makes a new variable? (a) make (b) put (c) give (d) let
7. 7.⚡ What number does this code print?
   let a = 27;
   let b = 10;
   console.log(a + b);
8. 8.⚡ What number does this code print?
   let coins = 28;
   coins = coins + 13;
   coins = coins - 23;
   console.log(coins);
9. 9.⚡ What does alert() show? (a) a picture (b) a table (c) a pop-up box (d) a new tab
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 1;
    console.log(x + y); (a) 9 (b) 81 (c) Error
11. 11.⚡ What number does this code print?
    let a = 50;
    let b = 9;
    console.log(a - b);
12. 12.⚡ Which JavaScript word repeats code? (a) if (b) console.log() (c) let (d) for
13. 13.⚡ Which JavaScript word makes a new variable? (a) let (b) for (c) alert() (d) console.log()
14. 14.⚡ What number does this code print?
    let score = 22;
    score = score + 7;
    score = score - 8;
    console.log(score);
15. 15.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) let (c) console.log() (d) for
16. 16.⚡ Which JavaScript word runs code when true? (a) for (b) if (c) alert() (d) let
17. 17.⚡ What number does this code print?
    let coins = 9;
    coins = coins + 19;
    coins = coins - 25;
    console.log(coins);
18. 18.⚡ What does JavaScript add to a web page? (a) the page title (b) actions and changes (c) only colours (d) the domain name
19. 19.⚡ What does this code show?
    let name = "Riya";
    alert("Welcome, " + name + "!"); (a) Welcome, Riya! (b) Riya (c) name (d) Welcome, name!
20. 20.⚡ What does this code show?
    let name = "Riya";
    alert("Well done, " + name + "!"); (a) Well done, name! (b) Riya (c) name (d) Well done, Riya!
21. 21.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .js (c) .css (d) .html
22. 22.⚡ What number does this code print?
    let score = 18;
    score = score + 20;
    score = score - 17;
    console.log(score);
23. 23.⚡ What number does this code print?
    let runs = 20;
    runs = runs + 9;
    runs = runs - 11;
    console.log(runs);
24. 24.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) name (b) Riya (c) Welcome, name! (d) Welcome, Riya!
25. 25.⚡ What does this code show?
    let name = "Arjun";
    alert("Welcome, " + name + "!"); (a) Welcome, name! (b) Welcome, Arjun! (c) name (d) Arjun
26. 26.⚡ What number does this code print?
    let a = 12;
    let b = 6;
    console.log(a - b);
27. 27.⚡ What number does this code print?
    let score = 12;
    score = score + 20;
    score = score - 8;
    console.log(score);
28. 28.⚡ What does this code show?
    let name = "Meera";
    alert("Hello, " + name + "!"); (a) Hello, Meera! (b) name (c) Meera (d) Hello, name!
29. 29.⚡ What number does this code print?
    let a = 23;
    let b = 22;
    console.log(a - b);
30. 30.⚡ What number does this code print?
    let a = 41;
    let b = 23;
    console.log(a + b);
31. 31.⚡ What number does this code print?
    let a = 48;
    let b = 22;
    console.log(a - b);
32. 32.⚡ What number does this code print?
    let a = 8;
    let b = 37;
    console.log(a + b);
33. 33.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 2;
    console.log(x + y); (a) 7 (b) 52 (c) Error
34. 34.⚡ What number does this code print?
    let a = 29;
    let b = 28;
    console.log(a - b);
35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 8;
    console.log(x + y); (a) 10 (b) Error (c) 28
36. 36.⚡ What number does this code print?
    let a = 53;
    let b = 35;
    console.log(a + b);
37. 37.⚡ What number does this code print?
    let a = 43;
    let b = 6;
    console.log(a + b);
38. 38.⚡ What number does this code print?
    let apples = 21;
    apples = apples + 7;
    apples = apples - 28;
    console.log(apples);
39. 39.⚡ What number does this code print?
    let a = 16;
    let b = 11;
    console.log(a - b);
40. 40.⚡ What does this code show?
    let name = "Aman";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) Hi, Aman! (c) name (d) Aman

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