JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 66 · 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 alert() show? (a) a new tab (b) a picture (c) a pop-up box (d) a table
2. 2.⚡ Which JavaScript word repeats code? (a) if (b) console.log() (c) alert() (d) for
3. 3.⚡ What number does this code print?
   let a = 4;
   let b = 11;
   console.log(a * b);
4. 4.⚡ Which JavaScript word runs code when true? (a) for (b) alert() (c) console.log() (d) if
5. 5.⚡ What number does this code print?
   let coins = 9;
   coins = coins + 17;
   coins = coins - 21;
   console.log(coins);
6. 6.⚡ What number does this code print?
   let coins = 21;
   coins = coins + 2;
   coins = coins - 13;
   console.log(coins);
7. 7.⚡ Which JavaScript word makes a new variable? (a) alert() (b) if (c) let (d) for
8. 8.⚡ Which JavaScript word writes in the console? (a) if (b) console.log() (c) alert() (d) let
9. 9.⚡ 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
10. 10.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) let (c) alert() (d) for
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 9;
    console.log(x + y); (a) 10 (b) 19 (c) Error
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 6;
    console.log(x + y); (a) 12 (b) 66 (c) Error
13. 13.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <js> (c) <style> (d) <script>
14. 14.⚡ What number does this code print?
    let a = 29;
    let b = 16;
    console.log(a - b);
15. 15.⚡ What number does this code print?
    let a = 48;
    let b = 18;
    console.log(a - b);
16. 16.⚡ What number does this code print?
    let a = 33;
    let b = 30;
    console.log(a - b);
17. 17.⚡ What number does this code print?
    let coins = 12;
    coins = coins + 20;
    coins = coins - 29;
    console.log(coins);
18. 18.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 3;
    console.log(x + y); (a) 4 (b) Error (c) 13
19. 19.⚡ What number does this code print?
    let a = 6;
    let b = 3;
    console.log(a * b);
20. 20.⚡ What number does this code print?
    let a = 10;
    let b = 9;
    console.log(a - b);
21. 21.⚡ What does this code show?
    let name = "Arjun";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Arjun (d) Hi, Arjun!
22. 22.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hi, " + name + "!"); (a) Kabir (b) Hi, name! (c) Hi, Kabir! (d) name
23. 23.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 8;
    console.log(x + y); (a) 38 (b) Error (c) 11
24. 24.⚡ What number does this code print?
    let score = 13;
    score = score + 18;
    score = score - 28;
    console.log(score);
25. 25.⚡ What number does this code print?
    let a = 11;
    let b = 5;
    console.log(a * b);
26. 26.⚡ What does this code show?
    let name = "Riya";
    alert("Welcome, " + name + "!"); (a) name (b) Riya (c) Welcome, Riya! (d) Welcome, name!
27. 27.⚡ What number does this code print?
    let books = 20;
    books = books + 11;
    books = books - 16;
    console.log(books);
28. 28.⚡ Which word makes a new variable? (a) let (b) put (c) give (d) make
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 7;
    console.log(x + y); (a) Error (b) 9 (c) 27
30. 30.⚡ What number does this code print?
    let a = 14;
    let b = 14;
    console.log(a - b);
31. 31.⚡ What does this code show?
    let name = "Aman";
    console.log("Hello, " + name + "!"); (a) Hello, Aman! (b) Hello, name! (c) Aman (d) name
32. 32.⚡ What does JavaScript add to a web page? (a) only colours (b) the domain name (c) the page title (d) actions and changes
33. 33.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!"); (a) Kabir (b) Hello, Kabir! (c) Hello, name! (d) name
34. 34.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!"); (a) name (b) Arjun (c) Hello, Arjun! (d) Hello, name!
35. 35.⚡ What number does this code print?
    let score = 28;
    score = score + 16;
    score = score - 3;
    console.log(score);
36. 36.⚡ What number does this code print?
    let a = 47;
    let b = 35;
    console.log(a - b);
37. 37.⚡ What does this code show?
    let name = "Meera";
    alert("Well done, " + name + "!"); (a) name (b) Well done, name! (c) Well done, Meera! (d) Meera
38. 38.⚡ What number does this code print?
    let marks = 25;
    marks = marks + 12;
    marks = marks - 19;
    console.log(marks);
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 4;
    console.log(x + y); (a) 74 (b) Error (c) 11
40. 40.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 1;
    console.log(x + y); (a) Error (b) 3 (c) 21

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