JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 878 · 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 number does this code print?
   let a = 40;
   let b = 16;
   console.log(a + b);
2. 2.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 3;
   console.log(x + y); (a) 5 (b) 23 (c) Error
3. 3.⚡ What does this code show?
   let name = "Riya";
   alert("Hello, " + name + "!"); (a) Riya (b) name (c) Hello, Riya! (d) Hello, name!
4. 4.⚡ 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
5. 5.⚡ What number does this code print?
   let apples = 11;
   apples = apples + 2;
   apples = apples - 13;
   console.log(apples);
6. 6.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 1;
   console.log(x + y); (a) Error (b) 21 (c) 3
7. 7.⚡ Which JavaScript word makes a new variable? (a) let (b) alert() (c) console.log() (d) for
8. 8.⚡ Which word makes a new variable? (a) let (b) put (c) make (d) give
9. 9.⚡ Which JavaScript word writes in the console? (a) for (b) console.log() (c) let (d) if
10. 10.⚡ What number does this code print?
    let a = 7;
    let b = 2;
    console.log(a * b);
11. 11.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Hi, Arjun! (d) Arjun
12. 12.⚡ What number does this code print?
    let a = 21;
    let b = 26;
    console.log(a + b);
13. 13.⚡ What number does this code print?
    let a = 12;
    let b = 8;
    console.log(a * b);
14. 14.⚡ What number does this code print?
    let a = 45;
    let b = 40;
    console.log(a + b);
15. 15.⚡ What number does this code print?
    let a = 9;
    let b = 7;
    console.log(a * b);
16. 16.⚡ What does this code show?
    let name = "Meera";
    console.log("Well done, " + name + "!"); (a) Meera (b) Well done, Meera! (c) name (d) Well done, name!
17. 17.⚡ What does this code show?
    let name = "Aman";
    alert("Well done, " + name + "!"); (a) Well done, Aman! (b) Well done, name! (c) Aman (d) name
18. 18.⚡ What number does this code print?
    let score = 25;
    score = score + 6;
    score = score - 14;
    console.log(score);
19. 19.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 6;
    console.log(x + y); (a) Error (b) 13 (c) 76
20. 20.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 3;
    console.log(x + y); (a) Error (b) 53 (c) 8
21. 21.⚡ Where does console.log() show its output? (a) on the title bar (b) in the console (c) in the address bar (d) on the printer
22. 22.⚡ What does alert() show? (a) a picture (b) a pop-up box (c) a new tab (d) a table
23. 23.⚡ What number does this code print?
    let a = 53;
    let b = 40;
    console.log(a + b);
24. 24.⚡ What number does this code print?
    let a = 24;
    let b = 9;
    console.log(a + b);
25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 3;
    console.log(x + y); (a) 6 (b) Error (c) 33
26. 26.⚡ What does this code show?
    let name = "Meera";
    alert("Hi, " + name + "!"); (a) Meera (b) Hi, name! (c) name (d) Hi, Meera!
27. 27.⚡ What number does this code print?
    let a = 54;
    let b = 10;
    console.log(a - b);
28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 5;
    console.log(x + y); (a) 9 (b) 45 (c) Error
29. 29.⚡ What number does this code print?
    let apples = 12;
    apples = apples + 15;
    apples = apples - 10;
    console.log(apples);
30. 30.⚡ What does JavaScript add to a web page? (a) the domain name (b) actions and changes (c) the page title (d) only colours
31. 31.⚡ Which JavaScript word shows a pop-up box? (a) if (b) for (c) alert() (d) console.log()
32. 32.⚡ What number does this code print?
    let a = 28;
    let b = 31;
    console.log(a + b);
33. 33.⚡ What number does this code print?
    let a = 44;
    let b = 20;
    console.log(a + b);
34. 34.⚡ What number does this code print?
    let coins = 7;
    coins = coins + 9;
    coins = coins - 6;
    console.log(coins);
35. 35.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .jpg (c) .css (d) .js
36. 36.⚡ What number does this code print?
    let marks = 22;
    marks = marks + 8;
    marks = marks - 16;
    console.log(marks);
37. 37.⚡ What number does this code print?
    let a = 24;
    let b = 36;
    console.log(a + b);
38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 4;
    console.log(x + y); (a) 34 (b) 7 (c) Error
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 9;
    console.log(x + y); (a) Error (b) 19 (c) 10
40. 40.⚡ What number does this code print?
    let runs = 10;
    runs = runs + 4;
    runs = runs - 2;
    console.log(runs);

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