JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 904 · 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 = "7";
   let y = 6;
   console.log(x + y); (a) 13 (b) 76 (c) Error
2. 2.⚡ What does this code show?
   let name = "Meera";
   console.log("Well done, " + name + "!"); (a) Well done, name! (b) Meera (c) name (d) Well done, Meera!
3. 3.⚡ What does this code show?
   let name = "Zoya";
   console.log("Hi, " + name + "!"); (a) Hi, Zoya! (b) Zoya (c) name (d) Hi, name!
4. 4.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .css (c) .jpg (d) .html
5. 5.⚡ What number does this code print?
   let books = 15;
   books = books + 5;
   books = books - 13;
   console.log(books);
6. 6.⚡ 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
7. 7.⚡ What does this code show?
   let name = "Aman";
   alert("Hi, " + name + "!"); (a) Aman (b) Hi, Aman! (c) name (d) Hi, name!
8. 8.⚡ What number does this code print?
   let score = 8;
   score = score + 2;
   score = score - 7;
   console.log(score);
9. 9.⚡ What does alert() show? (a) a pop-up box (b) a picture (c) a new tab (d) a table
10. 10.⚡ Which JavaScript word repeats code? (a) if (b) let (c) for (d) console.log()
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 2;
    console.log(x + y); (a) 12 (b) 3 (c) Error
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 3;
    console.log(x + y); (a) 6 (b) 33 (c) Error
13. 13.⚡ Which JavaScript word writes in the console? (a) let (b) console.log() (c) if (d) for
14. 14.⚡ What number does this code print?
    let coins = 12;
    coins = coins + 15;
    coins = coins - 18;
    console.log(coins);
15. 15.⚡ Where does console.log() show its output? (a) in the console (b) on the printer (c) on the title bar (d) in the address bar
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 7;
    console.log(x + y); (a) 57 (b) 12 (c) Error
17. 17.⚡ What number does this code print?
    let a = 6;
    let b = 5;
    console.log(a * b);
18. 18.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hello, " + name + "!"); (a) Arjun (b) name (c) Hello, Arjun! (d) Hello, name!
19. 19.⚡ What does JavaScript add to a web page? (a) the domain name (b) only colours (c) actions and changes (d) the page title
20. 20.⚡ What number does this code print?
    let a = 32;
    let b = 9;
    console.log(a - b);
21. 21.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 3;
    console.log(x + y); (a) 10 (b) Error (c) 73
22. 22.⚡ What number does this code print?
    let a = 9;
    let b = 3;
    console.log(a * b);
23. 23.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!"); (a) Hello, Kabir! (b) Kabir (c) Hello, name! (d) name
24. 24.⚡ What number does this code print?
    let score = 10;
    score = score + 6;
    score = score - 5;
    console.log(score);
25. 25.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) name (b) Meera (c) Hello, name! (d) Hello, Meera!
26. 26.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <code> (c) <script> (d) <js>
27. 27.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) Hi, name! (b) Hi, Riya! (c) Riya (d) name
28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 5;
    console.log(x + y); (a) Error (b) 6 (c) 15
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 6;
    console.log(x + y); (a) 8 (b) 26 (c) Error
30. 30.⚡ What number does this code print?
    let a = 12;
    let b = 14;
    console.log(a + b);
31. 31.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 8;
    console.log(x + y); (a) 98 (b) Error (c) 17
32. 32.⚡ What number does this code print?
    let coins = 25;
    coins = coins + 16;
    coins = coins - 5;
    console.log(coins);
33. 33.⚡ What does this code show?
    let name = "Meera";
    alert("Hi, " + name + "!"); (a) Meera (b) Hi, name! (c) Hi, Meera! (d) name
34. 34.⚡ Which JavaScript word runs code when true? (a) if (b) for (c) let (d) alert()
35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 1;
    console.log(x + y); (a) 7 (b) Error (c) 61
36. 36.⚡ What does this code show?
    let name = "Kabir";
    console.log("Welcome, " + name + "!"); (a) Welcome, Kabir! (b) name (c) Welcome, name! (d) Kabir
37. 37.⚡ What does this code show?
    let name = "Zoya";
    alert("Well done, " + name + "!"); (a) Well done, Zoya! (b) name (c) Well done, name! (d) Zoya
38. 38.⚡ What number does this code print?
    let a = 54;
    let b = 2;
    console.log(a - b);
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 5;
    console.log(x + y); (a) Error (b) 14 (c) 95
40. 40.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 6;
    console.log(x + y); (a) 66 (b) Error (c) 12

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