JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 725 · 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 apples = 5;
   apples = apples + 18;
   apples = apples - 2;
   console.log(apples);
2. 2.⚡ What number does this code print?
   let marks = 10;
   marks = marks + 12;
   marks = marks - 4;
   console.log(marks);
3. 3.⚡ Which JavaScript word writes in the console? (a) if (b) for (c) alert() (d) console.log()
4. 4.⚡ What number does this code print?
   let marks = 14;
   marks = marks + 4;
   marks = marks - 16;
   console.log(marks);
5. 5.⚡ What number does this code print?
   let a = 8;
   let b = 40;
   console.log(a + b);
6. 6.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 4;
   console.log(x + y); (a) Error (b) 9 (c) 54
7. 7.⚡ What does this code show?
   let name = "Arjun";
   console.log("Hi, " + name + "!"); (a) Hi, name! (b) Arjun (c) Hi, Arjun! (d) name
8. 8.⚡ 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
9. 9.⚡ 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
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 8;
    console.log(x + y); (a) 9 (b) Error (c) 18
11. 11.⚡ Which JavaScript word repeats code? (a) let (b) alert() (c) console.log() (d) for
12. 12.⚡ What does this code show?
    let name = "Meera";
    alert("Hi, " + name + "!"); (a) Meera (b) Hi, Meera! (c) Hi, name! (d) name
13. 13.⚡ What number does this code print?
    let a = 3;
    let b = 5;
    console.log(a * b);
14. 14.⚡ What does JavaScript add to a web page? (a) actions and changes (b) only colours (c) the page title (d) the domain name
15. 15.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) name (b) Hi, Riya! (c) Hi, name! (d) Riya
16. 16.⚡ What number does this code print?
    let books = 18;
    books = books + 2;
    books = books - 7;
    console.log(books);
17. 17.⚡ What number does this code print?
    let a = 19;
    let b = 3;
    console.log(a + b);
18. 18.⚡ What number does this code print?
    let apples = 6;
    apples = apples + 19;
    apples = apples - 25;
    console.log(apples);
19. 19.⚡ Which JavaScript word runs code when true? (a) for (b) if (c) console.log() (d) let
20. 20.⚡ Which word makes a new variable? (a) give (b) let (c) make (d) put
21. 21.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 1;
    console.log(x + y); (a) Error (b) 9 (c) 81
22. 22.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 3;
    console.log(x + y); (a) 13 (b) 4 (c) Error
23. 23.⚡ What number does this code print?
    let a = 49;
    let b = 15;
    console.log(a + b);
24. 24.⚡ What number does this code print?
    let a = 6;
    let b = 11;
    console.log(a * b);
25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 7;
    console.log(x + y); (a) Error (b) 8 (c) 17
26. 26.⚡ What number does this code print?
    let a = 44;
    let b = 3;
    console.log(a + b);
27. 27.⚡ What number does this code print?
    let a = 21;
    let b = 16;
    console.log(a - b);
28. 28.⚡ What number does this code print?
    let runs = 11;
    runs = runs + 15;
    runs = runs - 19;
    console.log(runs);
29. 29.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) name (c) Kabir (d) Hello, Kabir!
30. 30.⚡ What does alert() show? (a) a table (b) a picture (c) a pop-up box (d) a new tab
31. 31.⚡ What does this code show?
    let name = "Aman";
    alert("Well done, " + name + "!"); (a) Well done, name! (b) Aman (c) Well done, Aman! (d) name
32. 32.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .css (c) .jpg (d) .js
33. 33.⚡ What number does this code print?
    let a = 53;
    let b = 34;
    console.log(a - b);
34. 34.⚡ What number does this code print?
    let a = 60;
    let b = 3;
    console.log(a + b);
35. 35.⚡ What number does this code print?
    let books = 22;
    books = books + 16;
    books = books - 25;
    console.log(books);
36. 36.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) console.log() (c) for (d) let
37. 37.⚡ What number does this code print?
    let a = 30;
    let b = 9;
    console.log(a - b);
38. 38.⚡ 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
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 5;
    console.log(x + y); (a) Error (b) 13 (c) 85
40. 40.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <script> (c) <js> (d) <code>

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