JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 154 · 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 = "5";
   let y = 7;
   console.log(x + y); (a) Error (b) 12 (c) 57
2. 2.⚡ What number does this code print?
   let apples = 8;
   apples = apples + 8;
   apples = apples - 12;
   console.log(apples);
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 5;
   console.log(x + y); (a) 55 (b) Error (c) 10
4. 4.⚡ Which word makes a new variable? (a) let (b) give (c) put (d) make
5. 5.⚡ What does this code show?
   let name = "Aman";
   alert("Welcome, " + name + "!"); (a) name (b) Welcome, name! (c) Welcome, Aman! (d) Aman
6. 6.⚡ What does this code show?
   let name = "Meera";
   console.log("Welcome, " + name + "!"); (a) Meera (b) name (c) Welcome, name! (d) Welcome, Meera!
7. 7.⚡ Which JavaScript word writes in the console? (a) let (b) for (c) if (d) console.log()
8. 8.⚡ What number does this code print?
   let coins = 30;
   coins = coins + 4;
   coins = coins - 9;
   console.log(coins);
9. 9.⚡ Which JavaScript word runs code when true? (a) let (b) if (c) for (d) alert()
10. 10.⚡ What does this code show?
    let name = "Zoya";
    alert("Hello, " + name + "!"); (a) Hello, name! (b) Zoya (c) Hello, Zoya! (d) name
11. 11.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .js (c) .css (d) .html
12. 12.⚡ What does this code show?
    let name = "Meera";
    console.log("Hi, " + name + "!"); (a) Meera (b) name (c) Hi, Meera! (d) Hi, name!
13. 13.⚡ What number does this code print?
    let marks = 29;
    marks = marks + 20;
    marks = marks - 22;
    console.log(marks);
14. 14.⚡ What number does this code print?
    let marks = 9;
    marks = marks + 16;
    marks = marks - 21;
    console.log(marks);
15. 15.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <js> (c) <script> (d) <style>
16. 16.⚡ What number does this code print?
    let a = 15;
    let b = 14;
    console.log(a - b);
17. 17.⚡ What number does this code print?
    let a = 11;
    let b = 18;
    console.log(a + b);
18. 18.⚡ What does alert() show? (a) a picture (b) a pop-up box (c) a table (d) a new tab
19. 19.⚡ What number does this code print?
    let coins = 26;
    coins = coins + 15;
    coins = coins - 32;
    console.log(coins);
20. 20.⚡ Which JavaScript word repeats code? (a) alert() (b) console.log() (c) for (d) if
21. 21.⚡ What does JavaScript add to a web page? (a) the page title (b) the domain name (c) only colours (d) actions and changes
22. 22.⚡ What number does this code print?
    let coins = 9;
    coins = coins + 16;
    coins = coins - 2;
    console.log(coins);
23. 23.⚡ What number does this code print?
    let a = 14;
    let b = 7;
    console.log(a + b);
24. 24.⚡ What number does this code print?
    let books = 5;
    books = books + 13;
    books = books - 2;
    console.log(books);
25. 25.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hello, " + name + "!"); (a) Hello, Arjun! (b) name (c) Arjun (d) Hello, name!
26. 26.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) let (c) for (d) alert()
27. 27.⚡ What number does this code print?
    let marks = 24;
    marks = marks + 15;
    marks = marks - 2;
    console.log(marks);
28. 28.⚡ What number does this code print?
    let a = 4;
    let b = 6;
    console.log(a * b);
29. 29.⚡ What does this code show?
    let name = "Arjun";
    alert("Welcome, " + name + "!"); (a) Arjun (b) Welcome, name! (c) name (d) Welcome, Arjun!
30. 30.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Riya (d) Welcome, Riya!
31. 31.⚡ Where does console.log() show its output? (a) on the printer (b) in the console (c) on the title bar (d) in the address bar
32. 32.⚡ What does this code show?
    let name = "Zoya";
    alert("Hi, " + name + "!"); (a) name (b) Hi, Zoya! (c) Hi, name! (d) Zoya
33. 33.⚡ Which JavaScript word makes a new variable? (a) if (b) alert() (c) for (d) let
34. 34.⚡ What number does this code print?
    let apples = 19;
    apples = apples + 10;
    apples = apples - 20;
    console.log(apples);
35. 35.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hi, " + name + "!"); (a) name (b) Zoya (c) Hi, name! (d) Hi, Zoya!
36. 36.⚡ What number does this code print?
    let a = 17;
    let b = 14;
    console.log(a - b);
37. 37.⚡ What number does this code print?
    let a = 33;
    let b = 13;
    console.log(a + b);
38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 3;
    console.log(x + y); (a) 4 (b) Error (c) 13
39. 39.⚡ What number does this code print?
    let books = 12;
    books = books + 16;
    books = books - 18;
    console.log(books);
40. 40.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) Riya (b) name (c) Hi, name! (d) Hi, Riya!

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