JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 25 · 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 alert() show? (a) a picture (b) a pop-up box (c) a table (d) a new tab
2. 2.⚡ Which JavaScript word repeats code? (a) if (b) for (c) let (d) console.log()
3. 3.⚡ What does this code show?
   let name = "Arjun";
   alert("Well done, " + name + "!"); (a) Well done, name! (b) name (c) Well done, Arjun! (d) Arjun
4. 4.⚡ What number does this code print?
   let marks = 28;
   marks = marks + 15;
   marks = marks - 11;
   console.log(marks);
5. 5.⚡ What does this code print? (Look at the quotes!)
   let x = "7";
   let y = 2;
   console.log(x + y); (a) 72 (b) 9 (c) Error
6. 6.⚡ What does this code show?
   let name = "Zoya";
   console.log("Hi, " + name + "!"); (a) Zoya (b) Hi, name! (c) name (d) Hi, Zoya!
7. 7.⚡ What number does this code print?
   let a = 27;
   let b = 23;
   console.log(a - b);
8. 8.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <style> (c) <script> (d) <code>
9. 9.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .jpg (c) .js (d) .css
10. 10.⚡ What does this code show?
    let name = "Arjun";
    alert("Welcome, " + name + "!"); (a) name (b) Arjun (c) Welcome, name! (d) Welcome, Arjun!
11. 11.⚡ What does this code show?
    let name = "Aman";
    alert("Well done, " + name + "!"); (a) name (b) Well done, name! (c) Aman (d) Well done, Aman!
12. 12.⚡ Which JavaScript word makes a new variable? (a) alert() (b) let (c) for (d) console.log()
13. 13.⚡ What number does this code print?
    let coins = 7;
    coins = coins + 10;
    coins = coins - 3;
    console.log(coins);
14. 14.⚡ What number does this code print?
    let marks = 20;
    marks = marks + 2;
    marks = marks - 12;
    console.log(marks);
15. 15.⚡ What does this code show?
    let name = "Meera";
    alert("Hello, " + name + "!"); (a) name (b) Hello, Meera! (c) Meera (d) Hello, name!
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 8;
    console.log(x + y); (a) Error (b) 13 (c) 58
17. 17.⚡ What does this code show?
    let name = "Aman";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) Aman (c) Welcome, Aman! (d) name
18. 18.⚡ What number does this code print?
    let a = 5;
    let b = 23;
    console.log(a + b);
19. 19.⚡ What number does this code print?
    let score = 25;
    score = score + 20;
    score = score - 17;
    console.log(score);
20. 20.⚡ What number does this code print?
    let score = 24;
    score = score + 2;
    score = score - 11;
    console.log(score);
21. 21.⚡ What number does this code print?
    let a = 32;
    let b = 27;
    console.log(a + b);
22. 22.⚡ Where does console.log() show its output? (a) in the console (b) on the printer (c) in the address bar (d) on the title bar
23. 23.⚡ 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
24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 5;
    console.log(x + y); (a) 15 (b) Error (c) 6
25. 25.⚡ What number does this code print?
    let runs = 15;
    runs = runs + 6;
    runs = runs - 12;
    console.log(runs);
26. 26.⚡ Which JavaScript word shows a pop-up box? (a) for (b) console.log() (c) if (d) alert()
27. 27.⚡ Which JavaScript word writes in the console? (a) if (b) for (c) console.log() (d) alert()
28. 28.⚡ What number does this code print?
    let a = 4;
    let b = 12;
    console.log(a * b);
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 6;
    console.log(x + y); (a) 9 (b) 36 (c) Error
30. 30.⚡ What number does this code print?
    let a = 38;
    let b = 7;
    console.log(a - b);
31. 31.⚡ What does this code show?
    let name = "Meera";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) Meera (c) Welcome, Meera! (d) name
32. 32.⚡ What number does this code print?
    let a = 6;
    let b = 10;
    console.log(a + b);
33. 33.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 7;
    console.log(x + y); (a) 10 (b) Error (c) 37
34. 34.⚡ What number does this code print?
    let a = 27;
    let b = 8;
    console.log(a + b);
35. 35.⚡ What number does this code print?
    let a = 28;
    let b = 4;
    console.log(a - b);
36. 36.⚡ What does this code show?
    let name = "Arjun";
    console.log("Well done, " + name + "!"); (a) Arjun (b) Well done, Arjun! (c) name (d) Well done, name!
37. 37.⚡ What does this code show?
    let name = "Kabir";
    alert("Hi, " + name + "!"); (a) Hi, Kabir! (b) Hi, name! (c) Kabir (d) name
38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 6;
    console.log(x + y); (a) 7 (b) 16 (c) Error
39. 39.⚡ What number does this code print?
    let a = 47;
    let b = 3;
    console.log(a + b);
40. 40.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 1;
    console.log(x + y); (a) Error (b) 31 (c) 4

Free html and css lessons, practice and worksheets at talentjr.in/html-css-for-kids