JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 290 · 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 show?
   let name = "Riya";
   alert("Well done, " + name + "!"); (a) Well done, name! (b) name (c) Riya (d) Well done, Riya!
2. 2.⚡ What does this code print? (Look at the quotes!)
   let x = "7";
   let y = 2;
   console.log(x + y); (a) 72 (b) Error (c) 9
3. 3.⚡ Which JavaScript word repeats code? (a) alert() (b) for (c) console.log() (d) if
4. 4.⚡ What number does this code print?
   let a = 13;
   let b = 15;
   console.log(a + b);
5. 5.⚡ Where does console.log() show its output? (a) in the console (b) on the title bar (c) on the printer (d) in the address bar
6. 6.⚡ What number does this code print?
   let a = 4;
   let b = 5;
   console.log(a * b);
7. 7.⚡ Which word makes a new variable? (a) put (b) make (c) let (d) give
8. 8.⚡ What does JavaScript add to a web page? (a) only colours (b) the page title (c) actions and changes (d) the domain name
9. 9.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) if (c) alert() (d) for
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 4;
    console.log(x + y); (a) Error (b) 74 (c) 11
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 3;
    console.log(x + y); (a) 6 (b) 33 (c) Error
12. 12.⚡ What does alert() show? (a) a picture (b) a new tab (c) a table (d) a pop-up box
13. 13.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 7;
    console.log(x + y); (a) 11 (b) Error (c) 47
14. 14.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <js> (c) <code> (d) <style>
15. 15.⚡ What number does this code print?
    let a = 21;
    let b = 29;
    console.log(a + b);
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 3;
    console.log(x + y); (a) 10 (b) 73 (c) Error
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 6;
    console.log(x + y); (a) Error (b) 12 (c) 66
18. 18.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 4;
    console.log(x + y); (a) 12 (b) Error (c) 84
19. 19.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 8;
    console.log(x + y); (a) 11 (b) 38 (c) Error
20. 20.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 3;
    console.log(x + y); (a) Error (b) 43 (c) 7
21. 21.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!"); (a) Hello, name! (b) name (c) Arjun (d) Hello, Arjun!
22. 22.⚡ What does this code show?
    let name = "Zoya";
    console.log("Welcome, " + name + "!"); (a) Zoya (b) Welcome, name! (c) Welcome, Zoya! (d) name
23. 23.⚡ What number does this code print?
    let a = 39;
    let b = 25;
    console.log(a + b);
24. 24.⚡ What does this code show?
    let name = "Aman";
    console.log("Hi, " + name + "!"); (a) Hi, Aman! (b) Aman (c) name (d) Hi, name!
25. 25.⚡ What number does this code print?
    let score = 5;
    score = score + 9;
    score = score - 9;
    console.log(score);
26. 26.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 2;
    console.log(x + y); (a) 11 (b) Error (c) 92
27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 9;
    console.log(x + y); (a) 11 (b) 29 (c) Error
28. 28.⚡ What number does this code print?
    let books = 15;
    books = books + 12;
    books = books - 13;
    console.log(books);
29. 29.⚡ Which JavaScript word makes a new variable? (a) alert() (b) if (c) console.log() (d) let
30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 3;
    console.log(x + y); (a) Error (b) 83 (c) 11
31. 31.⚡ Which JavaScript word runs code when true? (a) alert() (b) let (c) console.log() (d) if
32. 32.⚡ What number does this code print?
    let a = 35;
    let b = 15;
    console.log(a + b);
33. 33.⚡ What number does this code print?
    let runs = 13;
    runs = runs + 7;
    runs = runs - 6;
    console.log(runs);
34. 34.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) Riya (b) Hi, name! (c) name (d) Hi, Riya!
35. 35.⚡ What does this code show?
    let name = "Zoya";
    alert("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Zoya (d) Welcome, Zoya!
36. 36.⚡ What number does this code print?
    let marks = 23;
    marks = marks + 3;
    marks = marks - 3;
    console.log(marks);
37. 37.⚡ What number does this code print?
    let a = 25;
    let b = 23;
    console.log(a - b);
38. 38.⚡ What number does this code print?
    let score = 25;
    score = score + 8;
    score = score - 5;
    console.log(score);
39. 39.⚡ What number does this code print?
    let coins = 8;
    coins = coins + 6;
    coins = coins - 4;
    console.log(coins);
40. 40.⚡ What number does this code print?
    let a = 39;
    let b = 27;
    console.log(a - b);

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