JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 411 · 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 printer (b) in the address bar (c) in the console (d) on the title bar
2. 2.⚡ What number does this code print?
   let a = 25;
   let b = 20;
   console.log(a + b);
3. 3.⚡ What does this code show?
   let name = "Kabir";
   console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) Kabir (c) Welcome, Kabir! (d) name
4. 4.⚡ What does this code show?
   let name = "Aman";
   console.log("Hello, " + name + "!"); (a) Aman (b) name (c) Hello, name! (d) Hello, Aman!
5. 5.⚡ What number does this code print?
   let score = 8;
   score = score + 8;
   score = score - 4;
   console.log(score);
6. 6.⚡ Which JavaScript word makes a new variable? (a) alert() (b) let (c) console.log() (d) if
7. 7.⚡ What does this code show?
   let name = "Zoya";
   console.log("Hi, " + name + "!"); (a) Hi, name! (b) Hi, Zoya! (c) name (d) Zoya
8. 8.⚡ What number does this code print?
   let runs = 30;
   runs = runs + 2;
   runs = runs - 30;
   console.log(runs);
9. 9.⚡ What does this code print? (Look at the quotes!)
   let x = "1";
   let y = 4;
   console.log(x + y); (a) 14 (b) Error (c) 5
10. 10.⚡ Which JavaScript word repeats code? (a) console.log() (b) if (c) let (d) for
11. 11.⚡ What number does this code print?
    let score = 5;
    score = score + 18;
    score = score - 23;
    console.log(score);
12. 12.⚡ What number does this code print?
    let score = 8;
    score = score + 6;
    score = score - 4;
    console.log(score);
13. 13.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .css (c) .jpg (d) .html
14. 14.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) console.log() (c) if (d) let
15. 15.⚡ Which JavaScript word runs code when true? (a) if (b) console.log() (c) for (d) let
16. 16.⚡ What does JavaScript add to a web page? (a) the page title (b) the domain name (c) only colours (d) actions and changes
17. 17.⚡ What number does this code print?
    let books = 6;
    books = books + 18;
    books = books - 23;
    console.log(books);
18. 18.⚡ Which JavaScript word writes in the console? (a) alert() (b) for (c) let (d) console.log()
19. 19.⚡ What does this code show?
    let name = "Riya";
    alert("Well done, " + name + "!"); (a) Well done, Riya! (b) name (c) Riya (d) Well done, name!
20. 20.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) Kabir (c) name (d) Hi, Kabir!
21. 21.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <js> (c) <script> (d) <style>
22. 22.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!"); (a) name (b) Kabir (c) Hello, name! (d) Hello, Kabir!
23. 23.⚡ What does alert() show? (a) a table (b) a new tab (c) a pop-up box (d) a picture
24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 9;
    console.log(x + y); (a) 13 (b) 49 (c) Error
25. 25.⚡ What number does this code print?
    let a = 48;
    let b = 34;
    console.log(a - b);
26. 26.⚡ What number does this code print?
    let a = 20;
    let b = 7;
    console.log(a - b);
27. 27.⚡ What does this code show?
    let name = "Zoya";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) Hi, Zoya! (c) name (d) Zoya
28. 28.⚡ What number does this code print?
    let a = 44;
    let b = 37;
    console.log(a - b);
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 6;
    console.log(x + y); (a) 9 (b) Error (c) 36
30. 30.⚡ What number does this code print?
    let marks = 27;
    marks = marks + 11;
    marks = marks - 24;
    console.log(marks);
31. 31.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 6;
    console.log(x + y); (a) 16 (b) Error (c) 7
32. 32.⚡ What does this code show?
    let name = "Aman";
    console.log("Well done, " + name + "!"); (a) Aman (b) Well done, name! (c) name (d) Well done, Aman!
33. 33.⚡ What number does this code print?
    let books = 29;
    books = books + 18;
    books = books - 44;
    console.log(books);
34. 34.⚡ What number does this code print?
    let apples = 14;
    apples = apples + 9;
    apples = apples - 10;
    console.log(apples);
35. 35.⚡ What number does this code print?
    let score = 30;
    score = score + 17;
    score = score - 11;
    console.log(score);
36. 36.⚡ What number does this code print?
    let a = 5;
    let b = 5;
    console.log(a * b);
37. 37.⚡ Which word makes a new variable? (a) let (b) give (c) put (d) make
38. 38.⚡ What number does this code print?
    let a = 27;
    let b = 23;
    console.log(a + b);
39. 39.⚡ What does this code show?
    let name = "Meera";
    alert("Hello, " + name + "!"); (a) name (b) Hello, Meera! (c) Meera (d) Hello, name!
40. 40.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!"); (a) Arjun (b) name (c) Hello, name! (d) Hello, Arjun!

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