JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 959 · 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 = "7";
   let y = 9;
   console.log(x + y); (a) 16 (b) 79 (c) Error
2. 2.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <style> (c) <js> (d) <script>
3. 3.⚡ What does this code show?
   let name = "Aman";
   alert("Hello, " + name + "!"); (a) name (b) Hello, Aman! (c) Aman (d) Hello, name!
4. 4.⚡ What number does this code print?
   let a = 3;
   let b = 7;
   console.log(a * b);
5. 5.⚡ What number does this code print?
   let score = 6;
   score = score + 4;
   score = score - 10;
   console.log(score);
6. 6.⚡ What number does this code print?
   let a = 23;
   let b = 14;
   console.log(a + b);
7. 7.⚡ What does this code show?
   let name = "Arjun";
   alert("Hi, " + name + "!"); (a) Hi, name! (b) Arjun (c) Hi, Arjun! (d) name
8. 8.⚡ Which JavaScript word writes in the console? (a) let (b) console.log() (c) if (d) for
9. 9.⚡ 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
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 5;
    console.log(x + y); (a) 8 (b) Error (c) 35
11. 11.⚡ Which JavaScript word runs code when true? (a) for (b) if (c) console.log() (d) let
12. 12.⚡ What number does this code print?
    let books = 18;
    books = books + 9;
    books = books - 26;
    console.log(books);
13. 13.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .css (c) .html (d) .js
14. 14.⚡ What does this code show?
    let name = "Aman";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) name (c) Aman (d) Hello, Aman!
15. 15.⚡ Which word makes a new variable? (a) let (b) make (c) give (d) put
16. 16.⚡ What does this code show?
    let name = "Arjun";
    alert("Well done, " + name + "!"); (a) Arjun (b) Well done, Arjun! (c) name (d) Well done, name!
17. 17.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) name (b) Riya (c) Welcome, Riya! (d) Welcome, name!
18. 18.⚡ Which JavaScript word repeats code? (a) for (b) let (c) if (d) console.log()
19. 19.⚡ What does JavaScript add to a web page? (a) the page title (b) actions and changes (c) the domain name (d) only colours
20. 20.⚡ Which JavaScript word shows a pop-up box? (a) for (b) let (c) if (d) alert()
21. 21.⚡ What does alert() show? (a) a picture (b) a pop-up box (c) a table (d) a new tab
22. 22.⚡ What does this code show?
    let name = "Zoya";
    alert("Hello, " + name + "!"); (a) Hello, Zoya! (b) name (c) Hello, name! (d) Zoya
23. 23.⚡ What does this code show?
    let name = "Zoya";
    alert("Welcome, " + name + "!"); (a) name (b) Welcome, Zoya! (c) Zoya (d) Welcome, name!
24. 24.⚡ What does this code show?
    let name = "Riya";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Riya (d) Hi, Riya!
25. 25.⚡ What number does this code print?
    let a = 4;
    let b = 9;
    console.log(a * b);
26. 26.⚡ What number does this code print?
    let a = 2;
    let b = 12;
    console.log(a * b);
27. 27.⚡ What does this code show?
    let name = "Zoya";
    alert("Hi, " + name + "!"); (a) name (b) Hi, Zoya! (c) Zoya (d) Hi, name!
28. 28.⚡ What does this code show?
    let name = "Aman";
    console.log("Hi, " + name + "!"); (a) Aman (b) Hi, Aman! (c) Hi, name! (d) name
29. 29.⚡ What does this code show?
    let name = "Aman";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) name (c) Aman (d) Well done, Aman!
30. 30.⚡ What number does this code print?
    let a = 4;
    let b = 5;
    console.log(a * b);
31. 31.⚡ Which JavaScript word makes a new variable? (a) alert() (b) let (c) console.log() (d) if
32. 32.⚡ What number does this code print?
    let a = 60;
    let b = 15;
    console.log(a + b);
33. 33.⚡ What number does this code print?
    let score = 14;
    score = score + 10;
    score = score - 10;
    console.log(score);
34. 34.⚡ What number does this code print?
    let a = 4;
    let b = 4;
    console.log(a * b);
35. 35.⚡ What number does this code print?
    let a = 20;
    let b = 13;
    console.log(a - b);
36. 36.⚡ What number does this code print?
    let a = 30;
    let b = 5;
    console.log(a - b);
37. 37.⚡ What number does this code print?
    let marks = 15;
    marks = marks + 3;
    marks = marks - 1;
    console.log(marks);
38. 38.⚡ What number does this code print?
    let a = 21;
    let b = 6;
    console.log(a - b);
39. 39.⚡ What number does this code print?
    let a = 17;
    let b = 40;
    console.log(a + b);
40. 40.⚡ What number does this code print?
    let a = 21;
    let b = 34;
    console.log(a + b);

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