JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 643 · 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 a = 33;
   let b = 5;
   console.log(a - b);
2. 2.⚡ What does this code show?
   let name = "Riya";
   console.log("Hello, " + name + "!"); (a) Riya (b) name (c) Hello, name! (d) Hello, Riya!
3. 3.⚡ Which JavaScript word makes a new variable? (a) console.log() (b) let (c) alert() (d) if
4. 4.⚡ What number does this code print?
   let runs = 21;
   runs = runs + 9;
   runs = runs - 26;
   console.log(runs);
5. 5.⚡ Which JavaScript word repeats code? (a) let (b) console.log() (c) for (d) if
6. 6.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 3;
   console.log(x + y); (a) 23 (b) Error (c) 5
7. 7.⚡ What number does this code print?
   let coins = 22;
   coins = coins + 13;
   coins = coins - 28;
   console.log(coins);
8. 8.⚡ Which JavaScript word shows a pop-up box? (a) if (b) for (c) let (d) alert()
9. 9.⚡ Which JavaScript word writes in the console? (a) console.log() (b) for (c) if (d) alert()
10. 10.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <style> (c) <script> (d) <js>
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 8;
    console.log(x + y); (a) 12 (b) Error (c) 48
12. 12.⚡ What does this code show?
    let name = "Aman";
    console.log("Well done, " + name + "!"); (a) Well done, Aman! (b) Aman (c) Well done, name! (d) name
13. 13.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 1;
    console.log(x + y); (a) Error (b) 41 (c) 5
14. 14.⚡ 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
15. 15.⚡ Where does console.log() show its output? (a) on the title bar (b) in the console (c) on the printer (d) in the address bar
16. 16.⚡ Which JavaScript word runs code when true? (a) for (b) alert() (c) if (d) let
17. 17.⚡ What does JavaScript add to a web page? (a) the page title (b) only colours (c) actions and changes (d) the domain name
18. 18.⚡ What number does this code print?
    let runs = 8;
    runs = runs + 8;
    runs = runs - 3;
    console.log(runs);
19. 19.⚡ What number does this code print?
    let books = 26;
    books = books + 19;
    books = books - 25;
    console.log(books);
20. 20.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .html (c) .js (d) .jpg
21. 21.⚡ What does this code show?
    let name = "Zoya";
    alert("Hello, " + name + "!"); (a) Hello, Zoya! (b) Zoya (c) name (d) Hello, name!
22. 22.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 2;
    console.log(x + y); (a) Error (b) 3 (c) 12
23. 23.⚡ What number does this code print?
    let a = 9;
    let b = 9;
    console.log(a * b);
24. 24.⚡ What number does this code print?
    let marks = 14;
    marks = marks + 15;
    marks = marks - 19;
    console.log(marks);
25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 4;
    console.log(x + y); (a) 6 (b) 24 (c) Error
26. 26.⚡ What number does this code print?
    let a = 16;
    let b = 17;
    console.log(a + b);
27. 27.⚡ What number does this code print?
    let a = 42;
    let b = 27;
    console.log(a + b);
28. 28.⚡ What does this code show?
    let name = "Zoya";
    console.log("Welcome, " + name + "!"); (a) name (b) Welcome, Zoya! (c) Zoya (d) Welcome, name!
29. 29.⚡ What does this code show?
    let name = "Riya";
    console.log("Well done, " + name + "!"); (a) Well done, Riya! (b) Riya (c) Well done, name! (d) name
30. 30.⚡ What number does this code print?
    let coins = 23;
    coins = coins + 9;
    coins = coins - 1;
    console.log(coins);
31. 31.⚡ Which word makes a new variable? (a) let (b) put (c) make (d) give
32. 32.⚡ What number does this code print?
    let apples = 7;
    apples = apples + 20;
    apples = apples - 1;
    console.log(apples);
33. 33.⚡ What does alert() show? (a) a pop-up box (b) a new tab (c) a table (d) a picture
34. 34.⚡ What does this code show?
    let name = "Arjun";
    console.log("Well done, " + name + "!"); (a) Arjun (b) Well done, name! (c) Well done, Arjun! (d) name
35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 1;
    console.log(x + y); (a) Error (b) 8 (c) 71
36. 36.⚡ What number does this code print?
    let a = 50;
    let b = 6;
    console.log(a + b);
37. 37.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 3;
    console.log(x + y); (a) 13 (b) Error (c) 4
38. 38.⚡ What number does this code print?
    let marks = 25;
    marks = marks + 18;
    marks = marks - 38;
    console.log(marks);
39. 39.⚡ What number does this code print?
    let a = 9;
    let b = 4;
    console.log(a * b);
40. 40.⚡ What number does this code print?
    let runs = 7;
    runs = runs + 4;
    runs = runs - 1;
    console.log(runs);

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