JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 714 · 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 coins = 29;
   coins = coins + 17;
   coins = coins - 19;
   console.log(coins);
2. 2.⚡ What number does this code print?
   let a = 21;
   let b = 17;
   console.log(a + b);
3. 3.⚡ Where does console.log() show its output? (a) in the address bar (b) in the console (c) on the title bar (d) on the printer
4. 4.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <script> (c) <style> (d) <code>
5. 5.⚡ What does this code print? (Look at the quotes!)
   let x = "1";
   let y = 7;
   console.log(x + y); (a) Error (b) 17 (c) 8
6. 6.⚡ Which JavaScript word repeats code? (a) alert() (b) for (c) console.log() (d) let
7. 7.⚡ Which JavaScript word runs code when true? (a) let (b) alert() (c) if (d) console.log()
8. 8.⚡ What does this code show?
   let name = "Aman";
   console.log("Well done, " + name + "!"); (a) Well done, Aman! (b) name (c) Aman (d) Well done, name!
9. 9.⚡ What does this code show?
   let name = "Zoya";
   console.log("Hello, " + name + "!"); (a) Zoya (b) name (c) Hello, name! (d) Hello, Zoya!
10. 10.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!"); (a) Hello, Arjun! (b) name (c) Hello, name! (d) Arjun
11. 11.⚡ What number does this code print?
    let a = 35;
    let b = 33;
    console.log(a + b);
12. 12.⚡ What number does this code print?
    let books = 6;
    books = books + 7;
    books = books - 10;
    console.log(books);
13. 13.⚡ Which word makes a new variable? (a) put (b) let (c) make (d) give
14. 14.⚡ What does JavaScript add to a web page? (a) the page title (b) the domain name (c) only colours (d) actions and changes
15. 15.⚡ What number does this code print?
    let coins = 23;
    coins = coins + 8;
    coins = coins - 19;
    console.log(coins);
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 5;
    console.log(x + y); (a) 95 (b) 14 (c) Error
17. 17.⚡ Which JavaScript word shows a pop-up box? (a) if (b) console.log() (c) let (d) alert()
18. 18.⚡ What does this code show?
    let name = "Arjun";
    alert("Hi, " + name + "!"); (a) Arjun (b) Hi, name! (c) name (d) Hi, Arjun!
19. 19.⚡ What does this code show?
    let name = "Meera";
    console.log("Welcome, " + name + "!"); (a) name (b) Welcome, name! (c) Welcome, Meera! (d) Meera
20. 20.⚡ Which JavaScript word writes in the console? (a) for (b) alert() (c) console.log() (d) if
21. 21.⚡ What does this code show?
    let name = "Riya";
    console.log("Hello, " + name + "!"); (a) Riya (b) Hello, Riya! (c) Hello, name! (d) name
22. 22.⚡ What number does this code print?
    let coins = 23;
    coins = coins + 13;
    coins = coins - 14;
    console.log(coins);
23. 23.⚡ What number does this code print?
    let a = 30;
    let b = 10;
    console.log(a + b);
24. 24.⚡ What number does this code print?
    let a = 7;
    let b = 4;
    console.log(a + b);
25. 25.⚡ What number does this code print?
    let books = 14;
    books = books + 20;
    books = books - 20;
    console.log(books);
26. 26.⚡ What does alert() show? (a) a table (b) a pop-up box (c) a new tab (d) a picture
27. 27.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) Riya (b) Hi, Riya! (c) Hi, name! (d) name
28. 28.⚡ What number does this code print?
    let score = 26;
    score = score + 14;
    score = score - 19;
    console.log(score);
29. 29.⚡ What number does this code print?
    let a = 49;
    let b = 4;
    console.log(a + b);
30. 30.⚡ What number does this code print?
    let a = 51;
    let b = 22;
    console.log(a - b);
31. 31.⚡ What number does this code print?
    let a = 19;
    let b = 18;
    console.log(a - b);
32. 32.⚡ What number does this code print?
    let a = 4;
    let b = 9;
    console.log(a * b);
33. 33.⚡ What number does this code print?
    let a = 39;
    let b = 9;
    console.log(a + b);
34. 34.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .jpg (c) .css (d) .js
35. 35.⚡ What number does this code print?
    let a = 51;
    let b = 13;
    console.log(a + b);
36. 36.⚡ What number does this code print?
    let a = 46;
    let b = 26;
    console.log(a - b);
37. 37.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 3;
    console.log(x + y); (a) 9 (b) 63 (c) Error
38. 38.⚡ What does this code show?
    let name = "Arjun";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) Arjun (c) name (d) Welcome, Arjun!
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 2;
    console.log(x + y); (a) 7 (b) Error (c) 52
40. 40.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 1;
    console.log(x + y); (a) 7 (b) 61 (c) Error

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