JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 207 · 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.⚡ Which JavaScript word writes in the console? (a) alert() (b) console.log() (c) for (d) let
2. 2.⚡ What number does this code print?
   let a = 12;
   let b = 4;
   console.log(a * b);
3. 3.⚡ Which word makes a new variable? (a) put (b) give (c) make (d) let
4. 4.⚡ What number does this code print?
   let a = 19;
   let b = 4;
   console.log(a - b);
5. 5.⚡ What number does this code print?
   let marks = 10;
   marks = marks + 16;
   marks = marks - 17;
   console.log(marks);
6. 6.⚡ What number does this code print?
   let a = 10;
   let b = 10;
   console.log(a * b);
7. 7.⚡ What does this code print? (Look at the quotes!)
   let x = "1";
   let y = 2;
   console.log(x + y); (a) 3 (b) 12 (c) Error
8. 8.⚡ What does JavaScript add to a web page? (a) the page title (b) only colours (c) actions and changes (d) the domain name
9. 9.⚡ What does this code show?
   let name = "Aman";
   alert("Hello, " + name + "!"); (a) name (b) Hello, Aman! (c) Aman (d) Hello, name!
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 7;
    console.log(x + y); (a) 11 (b) 47 (c) Error
11. 11.⚡ What number does this code print?
    let books = 5;
    books = books + 16;
    books = books - 14;
    console.log(books);
12. 12.⚡ Which JavaScript word repeats code? (a) let (b) console.log() (c) alert() (d) for
13. 13.⚡ Which JavaScript word makes a new variable? (a) for (b) let (c) alert() (d) console.log()
14. 14.⚡ What number does this code print?
    let a = 8;
    let b = 2;
    console.log(a * b);
15. 15.⚡ What does this code show?
    let name = "Arjun";
    alert("Well done, " + name + "!"); (a) Well done, name! (b) Well done, Arjun! (c) name (d) Arjun
16. 16.⚡ What number does this code print?
    let a = 46;
    let b = 9;
    console.log(a + b);
17. 17.⚡ What does alert() show? (a) a picture (b) a pop-up box (c) a table (d) a new tab
18. 18.⚡ What number does this code print?
    let a = 5;
    let b = 9;
    console.log(a * b);
19. 19.⚡ Which JavaScript word shows a pop-up box? (a) if (b) let (c) alert() (d) for
20. 20.⚡ What does this code show?
    let name = "Arjun";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Welcome, Arjun! (d) Arjun
21. 21.⚡ Which JavaScript word runs code when true? (a) alert() (b) if (c) for (d) let
22. 22.⚡ What number does this code print?
    let a = 10;
    let b = 8;
    console.log(a * b);
23. 23.⚡ What number does this code print?
    let a = 27;
    let b = 26;
    console.log(a - b);
24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 2;
    console.log(x + y); (a) Error (b) 42 (c) 6
25. 25.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <style> (c) <code> (d) <js>
26. 26.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 4;
    console.log(x + y); (a) Error (b) 84 (c) 12
27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 8;
    console.log(x + y); (a) 58 (b) Error (c) 13
28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 5;
    console.log(x + y); (a) 85 (b) Error (c) 13
29. 29.⚡ What does this code show?
    let name = "Kabir";
    alert("Well done, " + name + "!"); (a) Kabir (b) Well done, Kabir! (c) name (d) Well done, name!
30. 30.⚡ What number does this code print?
    let a = 53;
    let b = 2;
    console.log(a + b);
31. 31.⚡ What number does this code print?
    let runs = 22;
    runs = runs + 17;
    runs = runs - 11;
    console.log(runs);
32. 32.⚡ What number does this code print?
    let marks = 18;
    marks = marks + 14;
    marks = marks - 2;
    console.log(marks);
33. 33.⚡ What number does this code print?
    let a = 12;
    let b = 10;
    console.log(a * b);
34. 34.⚡ What number does this code print?
    let a = 23;
    let b = 10;
    console.log(a - b);
35. 35.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) Hi, Arjun! (c) Arjun (d) name
36. 36.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 9;
    console.log(x + y); (a) Error (b) 29 (c) 11
37. 37.⚡ Where does console.log() show its output? (a) in the console (b) in the address bar (c) on the printer (d) on the title bar
38. 38.⚡ What number does this code print?
    let runs = 12;
    runs = runs + 7;
    runs = runs - 12;
    console.log(runs);
39. 39.⚡ What does this code show?
    let name = "Meera";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) Meera (c) name (d) Hi, Meera!
40. 40.⚡ What number does this code print?
    let apples = 11;
    apples = apples + 6;
    apples = apples - 5;
    console.log(apples);

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