JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 266 · 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 = 31;
   let b = 15;
   console.log(a - b);
2. 2.⚡ What number does this code print?
   let a = 21;
   let b = 8;
   console.log(a + b);
3. 3.⚡ What does this code show?
   let name = "Riya";
   alert("Welcome, " + name + "!"); (a) Riya (b) name (c) Welcome, name! (d) Welcome, Riya!
4. 4.⚡ What does this code print? (Look at the quotes!)
   let x = "8";
   let y = 2;
   console.log(x + y); (a) 10 (b) 82 (c) Error
5. 5.⚡ 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
6. 6.⚡ What does alert() show? (a) a picture (b) a pop-up box (c) a new tab (d) a table
7. 7.⚡ Which JavaScript word repeats code? (a) console.log() (b) let (c) for (d) if
8. 8.⚡ What does this code show?
   let name = "Riya";
   console.log("Welcome, " + name + "!"); (a) name (b) Welcome, name! (c) Riya (d) Welcome, Riya!
9. 9.⚡ Which word makes a new variable? (a) give (b) make (c) put (d) let
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 8;
    console.log(x + y); (a) 17 (b) 98 (c) Error
11. 11.⚡ What number does this code print?
    let apples = 9;
    apples = apples + 11;
    apples = apples - 5;
    console.log(apples);
12. 12.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) Zoya (c) Hello, Zoya! (d) name
13. 13.⚡ What number does this code print?
    let a = 34;
    let b = 13;
    console.log(a + b);
14. 14.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 4;
    console.log(x + y); (a) 10 (b) 64 (c) Error
15. 15.⚡ What number does this code print?
    let books = 22;
    books = books + 14;
    books = books - 17;
    console.log(books);
16. 16.⚡ Which JavaScript word writes in the console? (a) if (b) alert() (c) console.log() (d) let
17. 17.⚡ Which JavaScript word makes a new variable? (a) let (b) for (c) if (d) alert()
18. 18.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .jpg (c) .js (d) .html
19. 19.⚡ What number does this code print?
    let a = 10;
    let b = 2;
    console.log(a + b);
20. 20.⚡ Which JavaScript word shows a pop-up box? (a) let (b) alert() (c) console.log() (d) for
21. 21.⚡ Where does console.log() show its output? (a) on the printer (b) on the title bar (c) in the console (d) in the address bar
22. 22.⚡ What does JavaScript add to a web page? (a) the page title (b) actions and changes (c) only colours (d) the domain name
23. 23.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) Meera (b) name (c) Hello, Meera! (d) Hello, name!
24. 24.⚡ What does this code show?
    let name = "Zoya";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Welcome, Zoya! (d) Zoya
25. 25.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!"); (a) Hello, name! (b) Riya (c) name (d) Hello, Riya!
26. 26.⚡ What number does this code print?
    let score = 13;
    score = score + 9;
    score = score - 12;
    console.log(score);
27. 27.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!"); (a) name (b) Hello, name! (c) Hello, Arjun! (d) Arjun
28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 8;
    console.log(x + y); (a) Error (b) 38 (c) 11
29. 29.⚡ What does this code show?
    let name = "Arjun";
    alert("Welcome, " + name + "!"); (a) Welcome, Arjun! (b) Welcome, name! (c) Arjun (d) name
30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 9;
    console.log(x + y); (a) 14 (b) Error (c) 59
31. 31.⚡ What number does this code print?
    let a = 2;
    let b = 3;
    console.log(a * b);
32. 32.⚡ What number does this code print?
    let apples = 19;
    apples = apples + 12;
    apples = apples - 10;
    console.log(apples);
33. 33.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 7;
    console.log(x + y); (a) 11 (b) 47 (c) Error
34. 34.⚡ What number does this code print?
    let coins = 19;
    coins = coins + 15;
    coins = coins - 33;
    console.log(coins);
35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 7;
    console.log(x + y); (a) Error (b) 97 (c) 16
36. 36.⚡ Which JavaScript word runs code when true? (a) if (b) for (c) console.log() (d) alert()
37. 37.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 9;
    console.log(x + y); (a) 17 (b) Error (c) 89
38. 38.⚡ What does this code show?
    let name = "Kabir";
    alert("Well done, " + name + "!"); (a) Well done, name! (b) name (c) Well done, Kabir! (d) Kabir
39. 39.⚡ What does this code show?
    let name = "Aman";
    alert("Hi, " + name + "!"); (a) name (b) Aman (c) Hi, Aman! (d) Hi, name!
40. 40.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 1;
    console.log(x + y); (a) Error (b) 51 (c) 6

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