JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 675 · 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 books = 5;
   books = books + 12;
   books = books - 4;
   console.log(books);
2. 2.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 7;
   console.log(x + y); (a) 27 (b) Error (c) 9
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "1";
   let y = 6;
   console.log(x + y); (a) Error (b) 7 (c) 16
4. 4.⚡ Which JavaScript word repeats code? (a) console.log() (b) for (c) alert() (d) let
5. 5.⚡ What number does this code print?
   let a = 12;
   let b = 2;
   console.log(a * b);
6. 6.⚡ What number does this code print?
   let a = 12;
   let b = 1;
   console.log(a + b);
7. 7.⚡ What number does this code print?
   let a = 11;
   let b = 11;
   console.log(a * b);
8. 8.⚡ Which JavaScript word makes a new variable? (a) if (b) alert() (c) let (d) for
9. 9.⚡ What number does this code print?
   let a = 5;
   let b = 11;
   console.log(a * b);
10. 10.⚡ What number does this code print?
    let score = 6;
    score = score + 7;
    score = score - 4;
    console.log(score);
11. 11.⚡ What number does this code print?
    let score = 24;
    score = score + 5;
    score = score - 1;
    console.log(score);
12. 12.⚡ Which JavaScript word writes in the console? (a) let (b) for (c) console.log() (d) if
13. 13.⚡ What number does this code print?
    let a = 4;
    let b = 2;
    console.log(a * b);
14. 14.⚡ What number does this code print?
    let books = 21;
    books = books + 8;
    books = books - 10;
    console.log(books);
15. 15.⚡ What number does this code print?
    let runs = 29;
    runs = runs + 16;
    runs = runs - 13;
    console.log(runs);
16. 16.⚡ What does this code show?
    let name = "Aman";
    alert("Hello, " + name + "!"); (a) Aman (b) Hello, Aman! (c) Hello, name! (d) name
17. 17.⚡ What number does this code print?
    let a = 17;
    let b = 35;
    console.log(a + b);
18. 18.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hi, " + name + "!"); (a) Zoya (b) Hi, name! (c) Hi, Zoya! (d) name
19. 19.⚡ Which JavaScript word shows a pop-up box? (a) let (b) console.log() (c) alert() (d) if
20. 20.⚡ What number does this code print?
    let a = 5;
    let b = 4;
    console.log(a * b);
21. 21.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 1;
    console.log(x + y); (a) 81 (b) 9 (c) Error
22. 22.⚡ What number does this code print?
    let a = 9;
    let b = 6;
    console.log(a - b);
23. 23.⚡ What number does this code print?
    let coins = 9;
    coins = coins + 2;
    coins = coins - 1;
    console.log(coins);
24. 24.⚡ What does this code show?
    let name = "Aman";
    console.log("Welcome, " + name + "!"); (a) Welcome, Aman! (b) Aman (c) name (d) Welcome, name!
25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 9;
    console.log(x + y); (a) Error (b) 14 (c) 59
26. 26.⚡ What does this code show?
    let name = "Aman";
    alert("Hi, " + name + "!"); (a) name (b) Hi, name! (c) Aman (d) Hi, Aman!
27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 7;
    console.log(x + y); (a) 17 (b) 8 (c) Error
28. 28.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <js> (c) <code> (d) <script>
29. 29.⚡ What does JavaScript add to a web page? (a) the page title (b) actions and changes (c) only colours (d) the domain name
30. 30.⚡ What number does this code print?
    let a = 12;
    let b = 6;
    console.log(a * b);
31. 31.⚡ 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
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 6;
    console.log(x + y); (a) Error (b) 8 (c) 26
33. 33.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 1;
    console.log(x + y); (a) Error (b) 5 (c) 41
34. 34.⚡ What does this code show?
    let name = "Meera";
    alert("Welcome, " + name + "!"); (a) Welcome, Meera! (b) Welcome, name! (c) Meera (d) name
35. 35.⚡ Which JavaScript word runs code when true? (a) if (b) for (c) let (d) console.log()
36. 36.⚡ Which word makes a new variable? (a) put (b) make (c) give (d) let
37. 37.⚡ What does this code show?
    let name = "Arjun";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) Arjun (c) name (d) Well done, Arjun!
38. 38.⚡ What number does this code print?
    let a = 6;
    let b = 12;
    console.log(a * b);
39. 39.⚡ What number does this code print?
    let a = 52;
    let b = 37;
    console.log(a - b);
40. 40.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .js (c) .jpg (d) .html

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