JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 572 · 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 books = 24;
   books = books + 2;
   books = books - 2;
   console.log(books);
2. 2.⚡ Which JavaScript word makes a new variable? (a) if (b) alert() (c) let (d) console.log()
3. 3.⚡ What does JavaScript add to a web page? (a) only colours (b) the page title (c) actions and changes (d) the domain name
4. 4.⚡ What does this code show?
   let name = "Aman";
   console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Aman (d) Welcome, Aman!
5. 5.⚡ What number does this code print?
   let a = 50;
   let b = 9;
   console.log(a + b);
6. 6.⚡ What number does this code print?
   let a = 39;
   let b = 26;
   console.log(a - b);
7. 7.⚡ What does alert() show? (a) a table (b) a new tab (c) a picture (d) a pop-up box
8. 8.⚡ Which JavaScript word runs code when true? (a) for (b) console.log() (c) let (d) if
9. 9.⚡ Which JavaScript word writes in the console? (a) let (b) for (c) console.log() (d) alert()
10. 10.⚡ What does this code show?
    let name = "Zoya";
    console.log("Well done, " + name + "!"); (a) name (b) Well done, name! (c) Well done, Zoya! (d) Zoya
11. 11.⚡ What number does this code print?
    let apples = 7;
    apples = apples + 19;
    apples = apples - 14;
    console.log(apples);
12. 12.⚡ What does this code show?
    let name = "Meera";
    alert("Well done, " + name + "!"); (a) name (b) Well done, name! (c) Well done, Meera! (d) Meera
13. 13.⚡ What number does this code print?
    let a = 6;
    let b = 3;
    console.log(a * b);
14. 14.⚡ Where does console.log() show its output? (a) in the console (b) on the title bar (c) in the address bar (d) on the printer
15. 15.⚡ What does this code show?
    let name = "Riya";
    console.log("Hello, " + name + "!"); (a) Riya (b) name (c) Hello, name! (d) Hello, Riya!
16. 16.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .html (c) .jpg (d) .css
17. 17.⚡ What number does this code print?
    let coins = 15;
    coins = coins + 17;
    coins = coins - 2;
    console.log(coins);
18. 18.⚡ Which JavaScript word shows a pop-up box? (a) for (b) alert() (c) if (d) let
19. 19.⚡ 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
20. 20.⚡ What number does this code print?
    let a = 4;
    let b = 9;
    console.log(a * b);
21. 21.⚡ What number does this code print?
    let coins = 17;
    coins = coins + 9;
    coins = coins - 25;
    console.log(coins);
22. 22.⚡ What number does this code print?
    let coins = 14;
    coins = coins + 7;
    coins = coins - 18;
    console.log(coins);
23. 23.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 4;
    console.log(x + y); (a) 44 (b) 8 (c) Error
24. 24.⚡ What number does this code print?
    let a = 37;
    let b = 5;
    console.log(a - b);
25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 5;
    console.log(x + y); (a) 35 (b) 8 (c) Error
26. 26.⚡ What number does this code print?
    let a = 9;
    let b = 26;
    console.log(a + b);
27. 27.⚡ Which word makes a new variable? (a) give (b) put (c) make (d) let
28. 28.⚡ What does this code show?
    let name = "Arjun";
    console.log("Well done, " + name + "!"); (a) Arjun (b) name (c) Well done, name! (d) Well done, Arjun!
29. 29.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <script> (c) <code> (d) <js>
30. 30.⚡ What number does this code print?
    let books = 26;
    books = books + 4;
    books = books - 2;
    console.log(books);
31. 31.⚡ What number does this code print?
    let runs = 17;
    runs = runs + 20;
    runs = runs - 26;
    console.log(runs);
32. 32.⚡ What number does this code print?
    let marks = 22;
    marks = marks + 9;
    marks = marks - 9;
    console.log(marks);
33. 33.⚡ What number does this code print?
    let score = 27;
    score = score + 7;
    score = score - 23;
    console.log(score);
34. 34.⚡ What does this code show?
    let name = "Kabir";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) Well done, Kabir! (c) Kabir (d) name
35. 35.⚡ What number does this code print?
    let a = 8;
    let b = 11;
    console.log(a * b);
36. 36.⚡ What number does this code print?
    let score = 28;
    score = score + 7;
    score = score - 29;
    console.log(score);
37. 37.⚡ What number does this code print?
    let a = 25;
    let b = 15;
    console.log(a + b);
38. 38.⚡ What number does this code print?
    let score = 28;
    score = score + 7;
    score = score - 24;
    console.log(score);
39. 39.⚡ Which JavaScript word repeats code? (a) alert() (b) if (c) for (d) let
40. 40.⚡ What number does this code print?
    let a = 43;
    let b = 21;
    console.log(a - b);

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