JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 633 · 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 score = 18;
   score = score + 11;
   score = score - 1;
   console.log(score);
2. 2.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <style> (c) <js> (d) <code>
3. 3.⚡ What number does this code print?
   let a = 51;
   let b = 11;
   console.log(a + b);
4. 4.⚡ Which JavaScript word writes in the console? (a) if (b) console.log() (c) for (d) let
5. 5.⚡ What number does this code print?
   let a = 11;
   let b = 11;
   console.log(a * b);
6. 6.⚡ Which JavaScript word shows a pop-up box? (a) for (b) let (c) if (d) alert()
7. 7.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 9;
   console.log(x + y); (a) Error (b) 59 (c) 14
8. 8.⚡ Which JavaScript word makes a new variable? (a) alert() (b) let (c) for (d) console.log()
9. 9.⚡ What does JavaScript add to a web page? (a) the domain name (b) the page title (c) only colours (d) actions and changes
10. 10.⚡ Where does console.log() show its output? (a) on the title bar (b) on the printer (c) in the address bar (d) in the console
11. 11.⚡ What does this code show?
    let name = "Meera";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) Welcome, Meera! (c) Meera (d) name
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 1;
    console.log(x + y); (a) Error (b) 10 (c) 91
13. 13.⚡ What does this code show?
    let name = "Riya";
    console.log("Hello, " + name + "!"); (a) Hello, Riya! (b) name (c) Riya (d) Hello, name!
14. 14.⚡ What number does this code print?
    let a = 10;
    let b = 11;
    console.log(a * b);
15. 15.⚡ What number does this code print?
    let score = 16;
    score = score + 16;
    score = score - 1;
    console.log(score);
16. 16.⚡ What does this code show?
    let name = "Arjun";
    console.log("Well done, " + name + "!"); (a) Arjun (b) name (c) Well done, Arjun! (d) Well done, name!
17. 17.⚡ What does this code show?
    let name = "Zoya";
    alert("Hello, " + name + "!"); (a) name (b) Zoya (c) Hello, Zoya! (d) Hello, name!
18. 18.⚡ What does alert() show? (a) a pop-up box (b) a table (c) a new tab (d) a picture
19. 19.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .html (c) .jpg (d) .css
20. 20.⚡ What number does this code print?
    let score = 15;
    score = score + 17;
    score = score - 14;
    console.log(score);
21. 21.⚡ What number does this code print?
    let a = 25;
    let b = 6;
    console.log(a - b);
22. 22.⚡ What number does this code print?
    let a = 6;
    let b = 7;
    console.log(a * b);
23. 23.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 7;
    console.log(x + y); (a) Error (b) 15 (c) 87
24. 24.⚡ Which JavaScript word runs code when true? (a) console.log() (b) if (c) for (d) let
25. 25.⚡ Which JavaScript word repeats code? (a) console.log() (b) if (c) for (d) let
26. 26.⚡ What does this code show?
    let name = "Arjun";
    alert("Well done, " + name + "!"); (a) name (b) Well done, Arjun! (c) Arjun (d) Well done, name!
27. 27.⚡ What number does this code print?
    let marks = 19;
    marks = marks + 5;
    marks = marks - 6;
    console.log(marks);
28. 28.⚡ What number does this code print?
    let a = 5;
    let b = 18;
    console.log(a + b);
29. 29.⚡ What number does this code print?
    let marks = 8;
    marks = marks + 11;
    marks = marks - 8;
    console.log(marks);
30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 1;
    console.log(x + y); (a) Error (b) 11 (c) 2
31. 31.⚡ What number does this code print?
    let books = 24;
    books = books + 4;
    books = books - 25;
    console.log(books);
32. 32.⚡ What number does this code print?
    let apples = 23;
    apples = apples + 8;
    apples = apples - 5;
    console.log(apples);
33. 33.⚡ What number does this code print?
    let a = 34;
    let b = 12;
    console.log(a - b);
34. 34.⚡ What number does this code print?
    let apples = 28;
    apples = apples + 3;
    apples = apples - 22;
    console.log(apples);
35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 8;
    console.log(x + y); (a) 78 (b) 15 (c) Error
36. 36.⚡ What number does this code print?
    let a = 12;
    let b = 10;
    console.log(a * b);
37. 37.⚡ What does this code show?
    let name = "Zoya";
    console.log("Welcome, " + name + "!"); (a) name (b) Welcome, Zoya! (c) Zoya (d) Welcome, name!
38. 38.⚡ 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
39. 39.⚡ What does this code show?
    let name = "Meera";
    alert("Hello, " + name + "!"); (a) name (b) Hello, name! (c) Hello, Meera! (d) Meera
40. 40.⚡ What number does this code print?
    let apples = 20;
    apples = apples + 8;
    apples = apples - 27;
    console.log(apples);

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