JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 702 · 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 does this code print? (Look at the quotes!)
   let x = "9";
   let y = 2;
   console.log(x + y); (a) 92 (b) 11 (c) Error
2. 2.⚡ What does JavaScript add to a web page? (a) only colours (b) the domain name (c) actions and changes (d) the page title
3. 3.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <style> (c) <code> (d) <js>
4. 4.⚡ Where does console.log() show its output? (a) on the printer (b) on the title bar (c) in the address bar (d) in the console
5. 5.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 4;
   console.log(x + y); (a) 9 (b) Error (c) 54
6. 6.⚡ Which JavaScript word writes in the console? (a) if (b) for (c) alert() (d) console.log()
7. 7.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .jpg (c) .js (d) .html
8. 8.⚡ What does this code show?
   let name = "Zoya";
   alert("Hello, " + name + "!"); (a) Zoya (b) Hello, name! (c) Hello, Zoya! (d) name
9. 9.⚡ What number does this code print?
   let a = 25;
   let b = 22;
   console.log(a + b);
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 8;
    console.log(x + y); (a) Error (b) 9 (c) 18
11. 11.⚡ Which JavaScript word shows a pop-up box? (a) for (b) alert() (c) let (d) if
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 7;
    console.log(x + y); (a) Error (b) 87 (c) 15
13. 13.⚡ Which word makes a new variable? (a) make (b) put (c) let (d) give
14. 14.⚡ What does this code show?
    let name = "Arjun";
    console.log("Welcome, " + name + "!"); (a) Welcome, Arjun! (b) name (c) Welcome, name! (d) Arjun
15. 15.⚡ What number does this code print?
    let score = 8;
    score = score + 17;
    score = score - 6;
    console.log(score);
16. 16.⚡ What number does this code print?
    let a = 6;
    let b = 10;
    console.log(a * b);
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 9;
    console.log(x + y); (a) Error (b) 11 (c) 29
18. 18.⚡ What number does this code print?
    let a = 11;
    let b = 1;
    console.log(a + b);
19. 19.⚡ What number does this code print?
    let books = 11;
    books = books + 7;
    books = books - 14;
    console.log(books);
20. 20.⚡ What does this code show?
    let name = "Aman";
    alert("Welcome, " + name + "!"); (a) Aman (b) name (c) Welcome, Aman! (d) Welcome, name!
21. 21.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 5;
    console.log(x + y); (a) 9 (b) Error (c) 45
22. 22.⚡ What number does this code print?
    let apples = 15;
    apples = apples + 7;
    apples = apples - 6;
    console.log(apples);
23. 23.⚡ What number does this code print?
    let runs = 12;
    runs = runs + 17;
    runs = runs - 16;
    console.log(runs);
24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 2;
    console.log(x + y); (a) 22 (b) 4 (c) Error
25. 25.⚡ What does this code show?
    let name = "Kabir";
    alert("Welcome, " + name + "!"); (a) Welcome, Kabir! (b) Welcome, name! (c) Kabir (d) name
26. 26.⚡ 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
27. 27.⚡ What number does this code print?
    let a = 6;
    let b = 11;
    console.log(a + b);
28. 28.⚡ 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
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 3;
    console.log(x + y); (a) 63 (b) Error (c) 9
30. 30.⚡ Which JavaScript word repeats code? (a) if (b) console.log() (c) alert() (d) for
31. 31.⚡ What number does this code print?
    let a = 21;
    let b = 37;
    console.log(a + b);
32. 32.⚡ What does alert() show? (a) a table (b) a pop-up box (c) a new tab (d) a picture
33. 33.⚡ Which JavaScript word runs code when true? (a) console.log() (b) if (c) for (d) alert()
34. 34.⚡ What number does this code print?
    let a = 21;
    let b = 7;
    console.log(a - b);
35. 35.⚡ What number does this code print?
    let a = 30;
    let b = 7;
    console.log(a + b);
36. 36.⚡ What number does this code print?
    let coins = 25;
    coins = coins + 4;
    coins = coins - 5;
    console.log(coins);
37. 37.⚡ What number does this code print?
    let a = 29;
    let b = 4;
    console.log(a + b);
38. 38.⚡ What number does this code print?
    let marks = 7;
    marks = marks + 7;
    marks = marks - 13;
    console.log(marks);
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 3;
    console.log(x + y); (a) 83 (b) 11 (c) Error
40. 40.⚡ What number does this code print?
    let a = 17;
    let b = 30;
    console.log(a + b);

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