JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 88 · 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 JavaScript word shows a pop-up box? (a) if (b) let (c) for (d) alert()
2. 2.⚡ What number does this code print?
   let a = 29;
   let b = 1;
   console.log(a + b);
3. 3.⚡ What number does this code print?
   let a = 4;
   let b = 3;
   console.log(a * b);
4. 4.⚡ Which JavaScript word runs code when true? (a) alert() (b) for (c) let (d) if
5. 5.⚡ What does alert() show? (a) a new tab (b) a pop-up box (c) a picture (d) a table
6. 6.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 4;
   console.log(x + y); (a) 54 (b) 9 (c) Error
7. 7.⚡ What number does this code print?
   let a = 18;
   let b = 23;
   console.log(a + b);
8. 8.⚡ Which JavaScript word writes in the console? (a) let (b) console.log() (c) for (d) alert()
9. 9.⚡ Which JavaScript word repeats code? (a) for (b) alert() (c) if (d) console.log()
10. 10.⚡ What does this code show?
    let name = "Arjun";
    alert("Hi, " + name + "!"); (a) name (b) Hi, name! (c) Arjun (d) Hi, Arjun!
11. 11.⚡ What number does this code print?
    let a = 4;
    let b = 5;
    console.log(a * b);
12. 12.⚡ Which word makes a new variable? (a) make (b) let (c) give (d) put
13. 13.⚡ What number does this code print?
    let a = 5;
    let b = 6;
    console.log(a * b);
14. 14.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 1;
    console.log(x + y); (a) 61 (b) 7 (c) Error
15. 15.⚡ What number does this code print?
    let a = 12;
    let b = 19;
    console.log(a + b);
16. 16.⚡ What does this code show?
    let name = "Kabir";
    console.log("Welcome, " + name + "!"); (a) name (b) Kabir (c) Welcome, name! (d) Welcome, Kabir!
17. 17.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <js> (c) <code> (d) <script>
18. 18.⚡ What number does this code print?
    let coins = 11;
    coins = coins + 19;
    coins = coins - 6;
    console.log(coins);
19. 19.⚡ What number does this code print?
    let a = 15;
    let b = 13;
    console.log(a + b);
20. 20.⚡ What number does this code print?
    let a = 12;
    let b = 8;
    console.log(a * b);
21. 21.⚡ What number does this code print?
    let a = 5;
    let b = 12;
    console.log(a * b);
22. 22.⚡ What number does this code print?
    let a = 7;
    let b = 8;
    console.log(a * b);
23. 23.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 8;
    console.log(x + y); (a) 17 (b) 98 (c) Error
24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 2;
    console.log(x + y); (a) 62 (b) Error (c) 8
25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 4;
    console.log(x + y); (a) Error (b) 6 (c) 24
26. 26.⚡ What number does this code print?
    let a = 20;
    let b = 17;
    console.log(a - b);
27. 27.⚡ What does this code show?
    let name = "Kabir";
    alert("Welcome, " + name + "!"); (a) Welcome, name! (b) Welcome, Kabir! (c) name (d) Kabir
28. 28.⚡ What does JavaScript add to a web page? (a) the page title (b) actions and changes (c) the domain name (d) only colours
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 5;
    console.log(x + y); (a) 85 (b) Error (c) 13
30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 1;
    console.log(x + y); (a) Error (b) 6 (c) 51
31. 31.⚡ What number does this code print?
    let a = 35;
    let b = 29;
    console.log(a - b);
32. 32.⚡ What number does this code print?
    let runs = 7;
    runs = runs + 4;
    runs = runs - 8;
    console.log(runs);
33. 33.⚡ What number does this code print?
    let runs = 17;
    runs = runs + 16;
    runs = runs - 8;
    console.log(runs);
34. 34.⚡ What does this code show?
    let name = "Meera";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) Well done, Meera! (c) name (d) Meera
35. 35.⚡ What number does this code print?
    let runs = 16;
    runs = runs + 14;
    runs = runs - 2;
    console.log(runs);
36. 36.⚡ What number does this code print?
    let a = 27;
    let b = 26;
    console.log(a - b);
37. 37.⚡ What number does this code print?
    let a = 29;
    let b = 20;
    console.log(a + b);
38. 38.⚡ What number does this code print?
    let marks = 27;
    marks = marks + 5;
    marks = marks - 1;
    console.log(marks);
39. 39.⚡ Where does console.log() show its output? (a) in the console (b) on the title bar (c) on the printer (d) in the address bar
40. 40.⚡ What number does this code print?
    let a = 49;
    let b = 9;
    console.log(a - b);

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