JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 269 · 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.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <style> (c) <js> (d) <code>
2. 2.⚡ What does this code show?
   let name = "Riya";
   alert("Hello, " + name + "!"); (a) Riya (b) name (c) Hello, Riya! (d) Hello, name!
3. 3.⚡ What number does this code print?
   let a = 12;
   let b = 12;
   console.log(a * b);
4. 4.⚡ What does this code print? (Look at the quotes!)
   let x = "7";
   let y = 1;
   console.log(x + y); (a) Error (b) 71 (c) 8
5. 5.⚡ Which JavaScript word writes in the console? (a) if (b) alert() (c) console.log() (d) for
6. 6.⚡ What number does this code print?
   let coins = 7;
   coins = coins + 12;
   coins = coins - 3;
   console.log(coins);
7. 7.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .jpg (c) .js (d) .css
8. 8.⚡ What number does this code print?
   let a = 56;
   let b = 20;
   console.log(a - b);
9. 9.⚡ What number does this code print?
   let a = 53;
   let b = 38;
   console.log(a + b);
10. 10.⚡ What number does this code print?
    let score = 27;
    score = score + 15;
    score = score - 34;
    console.log(score);
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 3;
    console.log(x + y); (a) Error (b) 6 (c) 33
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 9;
    console.log(x + y); (a) 11 (b) Error (c) 29
13. 13.⚡ What number does this code print?
    let a = 9;
    let b = 8;
    console.log(a * b);
14. 14.⚡ Which JavaScript word repeats code? (a) let (b) console.log() (c) alert() (d) for
15. 15.⚡ Which word makes a new variable? (a) make (b) put (c) give (d) let
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 7;
    console.log(x + y); (a) Error (b) 13 (c) 67
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 3;
    console.log(x + y); (a) Error (b) 5 (c) 23
18. 18.⚡ What does this code show?
    let name = "Meera";
    console.log("Welcome, " + name + "!"); (a) Welcome, Meera! (b) name (c) Meera (d) Welcome, name!
19. 19.⚡ What does alert() show? (a) a picture (b) a new tab (c) a pop-up box (d) a table
20. 20.⚡ What number does this code print?
    let books = 25;
    books = books + 16;
    books = books - 30;
    console.log(books);
21. 21.⚡ What number does this code print?
    let score = 18;
    score = score + 6;
    score = score - 4;
    console.log(score);
22. 22.⚡ What does this code show?
    let name = "Aman";
    console.log("Hello, " + name + "!"); (a) name (b) Hello, Aman! (c) Aman (d) Hello, name!
23. 23.⚡ What number does this code print?
    let a = 12;
    let b = 1;
    console.log(a + b);
24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 8;
    console.log(x + y); (a) 9 (b) 18 (c) Error
25. 25.⚡ What number does this code print?
    let a = 52;
    let b = 26;
    console.log(a - b);
26. 26.⚡ What number does this code print?
    let a = 57;
    let b = 35;
    console.log(a - b);
27. 27.⚡ What does this code show?
    let name = "Zoya";
    alert("Well done, " + name + "!"); (a) Zoya (b) Well done, Zoya! (c) Well done, name! (d) name
28. 28.⚡ What does this code show?
    let name = "Meera";
    alert("Welcome, " + name + "!"); (a) name (b) Meera (c) Welcome, Meera! (d) Welcome, name!
29. 29.⚡ Which JavaScript word makes a new variable? (a) console.log() (b) alert() (c) for (d) let
30. 30.⚡ What number does this code print?
    let a = 36;
    let b = 27;
    console.log(a - b);
31. 31.⚡ What number does this code print?
    let marks = 14;
    marks = marks + 10;
    marks = marks - 17;
    console.log(marks);
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 9;
    console.log(x + y); (a) 16 (b) 79 (c) Error
33. 33.⚡ What does this code show?
    let name = "Kabir";
    console.log("Welcome, " + name + "!"); (a) Kabir (b) Welcome, name! (c) Welcome, Kabir! (d) name
34. 34.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) let (c) for (d) if
35. 35.⚡ What number does this code print?
    let books = 20;
    books = books + 20;
    books = books - 1;
    console.log(books);
36. 36.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 2;
    console.log(x + y); (a) 10 (b) Error (c) 82
37. 37.⚡ What number does this code print?
    let a = 3;
    let b = 9;
    console.log(a * b);
38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 4;
    console.log(x + y); (a) 64 (b) 10 (c) Error
39. 39.⚡ What does this code show?
    let name = "Kabir";
    console.log("Well done, " + name + "!"); (a) name (b) Well done, Kabir! (c) Well done, name! (d) Kabir
40. 40.⚡ What number does this code print?
    let coins = 28;
    coins = coins + 2;
    coins = coins - 4;
    console.log(coins);

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