JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 956 · 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 writes in the console? (a) console.log() (b) for (c) alert() (d) let
2. 2.⚡ What does alert() show? (a) a picture (b) a new tab (c) a table (d) a pop-up box
3. 3.⚡ What number does this code print?
   let a = 27;
   let b = 10;
   console.log(a - b);
4. 4.⚡ What number does this code print?
   let apples = 7;
   apples = apples + 5;
   apples = apples - 12;
   console.log(apples);
5. 5.⚡ Where does console.log() show its output? (a) on the title bar (b) on the printer (c) in the address bar (d) in the console
6. 6.⚡ What does this code print? (Look at the quotes!)
   let x = "9";
   let y = 8;
   console.log(x + y); (a) 98 (b) 17 (c) Error
7. 7.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .jpg (c) .css (d) .js
8. 8.⚡ What number does this code print?
   let score = 17;
   score = score + 2;
   score = score - 17;
   console.log(score);
9. 9.⚡ Which JavaScript word runs code when true? (a) let (b) console.log() (c) alert() (d) if
10. 10.⚡ What does this code show?
    let name = "Meera";
    console.log("Well done, " + name + "!"); (a) Well done, Meera! (b) Meera (c) Well done, name! (d) name
11. 11.⚡ What number does this code print?
    let runs = 12;
    runs = runs + 8;
    runs = runs - 16;
    console.log(runs);
12. 12.⚡ What number does this code print?
    let apples = 10;
    apples = apples + 9;
    apples = apples - 5;
    console.log(apples);
13. 13.⚡ What number does this code print?
    let a = 5;
    let b = 5;
    console.log(a * b);
14. 14.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 3;
    console.log(x + y); (a) 43 (b) 7 (c) Error
15. 15.⚡ Which JavaScript word repeats code? (a) console.log() (b) alert() (c) if (d) for
16. 16.⚡ What number does this code print?
    let a = 31;
    let b = 21;
    console.log(a - b);
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 5;
    console.log(x + y); (a) 13 (b) Error (c) 85
18. 18.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) if (c) alert() (d) for
19. 19.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 6;
    console.log(x + y); (a) 7 (b) Error (c) 16
20. 20.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) Meera (b) name (c) Hello, Meera! (d) Hello, name!
21. 21.⚡ What number does this code print?
    let apples = 5;
    apples = apples + 17;
    apples = apples - 15;
    console.log(apples);
22. 22.⚡ Which word makes a new variable? (a) put (b) let (c) make (d) give
23. 23.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!"); (a) Hello, name! (b) Hello, Riya! (c) Riya (d) name
24. 24.⚡ What number does this code print?
    let coins = 19;
    coins = coins + 4;
    coins = coins - 3;
    console.log(coins);
25. 25.⚡ What number does this code print?
    let a = 36;
    let b = 10;
    console.log(a + b);
26. 26.⚡ What number does this code print?
    let books = 23;
    books = books + 14;
    books = books - 5;
    console.log(books);
27. 27.⚡ What number does this code print?
    let a = 9;
    let b = 5;
    console.log(a - b);
28. 28.⚡ What number does this code print?
    let coins = 6;
    coins = coins + 13;
    coins = coins - 17;
    console.log(coins);
29. 29.⚡ What number does this code print?
    let coins = 25;
    coins = coins + 18;
    coins = coins - 28;
    console.log(coins);
30. 30.⚡ What does JavaScript add to a web page? (a) the domain name (b) the page title (c) actions and changes (d) only colours
31. 31.⚡ Which JavaScript word makes a new variable? (a) let (b) alert() (c) console.log() (d) for
32. 32.⚡ What number does this code print?
    let a = 49;
    let b = 9;
    console.log(a - b);
33. 33.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 3;
    console.log(x + y); (a) Error (b) 83 (c) 11
34. 34.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <code> (c) <style> (d) <js>
35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 2;
    console.log(x + y); (a) 92 (b) Error (c) 11
36. 36.⚡ What number does this code print?
    let books = 10;
    books = books + 18;
    books = books - 13;
    console.log(books);
37. 37.⚡ What number does this code print?
    let a = 40;
    let b = 26;
    console.log(a + b);
38. 38.⚡ What number does this code print?
    let a = 54;
    let b = 2;
    console.log(a + b);
39. 39.⚡ What number does this code print?
    let a = 12;
    let b = 3;
    console.log(a - b);
40. 40.⚡ What number does this code print?
    let a = 5;
    let b = 10;
    console.log(a * b);

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