JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 117 · 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 print? (Look at the quotes!)
   let x = "1";
   let y = 9;
   console.log(x + y); (a) 10 (b) Error (c) 19
2. 2.⚡ Which JavaScript word runs code when true? (a) console.log() (b) if (c) alert() (d) let
3. 3.⚡ What does this code show?
   let name = "Aman";
   alert("Welcome, " + name + "!"); (a) Welcome, name! (b) Welcome, Aman! (c) name (d) Aman
4. 4.⚡ Which JavaScript word makes a new variable? (a) for (b) let (c) console.log() (d) alert()
5. 5.⚡ Which JavaScript word repeats code? (a) if (b) for (c) console.log() (d) let
6. 6.⚡ Which word makes a new variable? (a) make (b) put (c) give (d) let
7. 7.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <code> (c) <style> (d) <js>
8. 8.⚡ What number does this code print?
   let a = 10;
   let b = 9;
   console.log(a * b);
9. 9.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .jpg (c) .html (d) .js
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 4;
    console.log(x + y); (a) 5 (b) Error (c) 14
11. 11.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) name (b) Hello, name! (c) Meera (d) Hello, Meera!
12. 12.⚡ What number does this code print?
    let a = 21;
    let b = 6;
    console.log(a - b);
13. 13.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) if (c) alert() (d) let
14. 14.⚡ What number does this code print?
    let coins = 8;
    coins = coins + 20;
    coins = coins - 3;
    console.log(coins);
15. 15.⚡ What does this code show?
    let name = "Arjun";
    alert("Welcome, " + name + "!"); (a) Welcome, Arjun! (b) name (c) Arjun (d) Welcome, name!
16. 16.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hi, " + name + "!"); (a) name (b) Hi, name! (c) Zoya (d) Hi, Zoya!
17. 17.⚡ What number does this code print?
    let score = 21;
    score = score + 6;
    score = score - 19;
    console.log(score);
18. 18.⚡ What number does this code print?
    let coins = 17;
    coins = coins + 3;
    coins = coins - 3;
    console.log(coins);
19. 19.⚡ What does JavaScript add to a web page? (a) the domain name (b) the page title (c) actions and changes (d) only colours
20. 20.⚡ 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
21. 21.⚡ What number does this code print?
    let a = 6;
    let b = 6;
    console.log(a * b);
22. 22.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 9;
    console.log(x + y); (a) 49 (b) 13 (c) Error
23. 23.⚡ What does this code show?
    let name = "Zoya";
    alert("Hi, " + name + "!"); (a) Hi, Zoya! (b) name (c) Zoya (d) Hi, name!
24. 24.⚡ What number does this code print?
    let a = 57;
    let b = 21;
    console.log(a + b);
25. 25.⚡ What number does this code print?
    let a = 7;
    let b = 6;
    console.log(a * b);
26. 26.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 5;
    console.log(x + y); (a) 10 (b) 55 (c) Error
27. 27.⚡ Which JavaScript word writes in the console? (a) console.log() (b) if (c) alert() (d) let
28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 7;
    console.log(x + y); (a) 27 (b) 9 (c) Error
29. 29.⚡ What number does this code print?
    let marks = 24;
    marks = marks + 17;
    marks = marks - 18;
    console.log(marks);
30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 9;
    console.log(x + y); (a) Error (b) 16 (c) 79
31. 31.⚡ What number does this code print?
    let a = 14;
    let b = 2;
    console.log(a + b);
32. 32.⚡ What does this code show?
    let name = "Riya";
    console.log("Hello, " + name + "!"); (a) name (b) Riya (c) Hello, name! (d) Hello, Riya!
33. 33.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 6;
    console.log(x + y); (a) Error (b) 10 (c) 46
34. 34.⚡ What does this code show?
    let name = "Meera";
    alert("Hi, " + name + "!"); (a) name (b) Hi, Meera! (c) Hi, name! (d) Meera
35. 35.⚡ What does this code show?
    let name = "Aman";
    alert("Hi, " + name + "!"); (a) name (b) Hi, Aman! (c) Hi, name! (d) Aman
36. 36.⚡ What does alert() show? (a) a new tab (b) a table (c) a pop-up box (d) a picture
37. 37.⚡ What number does this code print?
    let a = 14;
    let b = 30;
    console.log(a + b);
38. 38.⚡ What number does this code print?
    let score = 8;
    score = score + 4;
    score = score - 11;
    console.log(score);
39. 39.⚡ What number does this code print?
    let a = 24;
    let b = 6;
    console.log(a - b);
40. 40.⚡ What number does this code print?
    let marks = 6;
    marks = marks + 6;
    marks = marks - 11;
    console.log(marks);

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