JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 243 · 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 = 11;
   let b = 24;
   console.log(a + b);
2. 2.⚡ What does this code show?
   let name = "Aman";
   alert("Welcome, " + name + "!"); (a) Welcome, Aman! (b) name (c) Aman (d) Welcome, name!
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 7;
   console.log(x + y); (a) 12 (b) 57 (c) Error
4. 4.⚡ What number does this code print?
   let runs = 16;
   runs = runs + 2;
   runs = runs - 4;
   console.log(runs);
5. 5.⚡ What does this code print? (Look at the quotes!)
   let x = "7";
   let y = 7;
   console.log(x + y); (a) 77 (b) 14 (c) Error
6. 6.⚡ What does this code print? (Look at the quotes!)
   let x = "8";
   let y = 2;
   console.log(x + y); (a) 82 (b) Error (c) 10
7. 7.⚡ Which JavaScript word writes in the console? (a) console.log() (b) for (c) if (d) let
8. 8.⚡ What does this code show?
   let name = "Meera";
   console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) Meera (c) Welcome, Meera! (d) name
9. 9.⚡ What number does this code print?
   let score = 6;
   score = score + 19;
   score = score - 25;
   console.log(score);
10. 10.⚡ What number does this code print?
    let books = 16;
    books = books + 18;
    books = books - 6;
    console.log(books);
11. 11.⚡ What number does this code print?
    let a = 15;
    let b = 12;
    console.log(a - b);
12. 12.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .js (c) .jpg (d) .html
13. 13.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 9;
    console.log(x + y); (a) Error (b) 10 (c) 19
14. 14.⚡ What number does this code print?
    let a = 2;
    let b = 11;
    console.log(a * b);
15. 15.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <script> (c) <js> (d) <code>
16. 16.⚡ What number does this code print?
    let books = 6;
    books = books + 18;
    books = books - 21;
    console.log(books);
17. 17.⚡ Which JavaScript word makes a new variable? (a) for (b) console.log() (c) let (d) if
18. 18.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 2;
    console.log(x + y); (a) 8 (b) 62 (c) Error
19. 19.⚡ What number does this code print?
    let a = 2;
    let b = 5;
    console.log(a * b);
20. 20.⚡ Which JavaScript word shows a pop-up box? (a) if (b) console.log() (c) alert() (d) let
21. 21.⚡ What number does this code print?
    let apples = 7;
    apples = apples + 13;
    apples = apples - 13;
    console.log(apples);
22. 22.⚡ Where does console.log() show its output? (a) in the address bar (b) in the console (c) on the title bar (d) on the printer
23. 23.⚡ Which JavaScript word runs code when true? (a) for (b) let (c) alert() (d) if
24. 24.⚡ What does JavaScript add to a web page? (a) the domain name (b) the page title (c) actions and changes (d) only colours
25. 25.⚡ What number does this code print?
    let coins = 23;
    coins = coins + 7;
    coins = coins - 9;
    console.log(coins);
26. 26.⚡ What number does this code print?
    let marks = 26;
    marks = marks + 20;
    marks = marks - 23;
    console.log(marks);
27. 27.⚡ What number does this code print?
    let coins = 13;
    coins = coins + 19;
    coins = coins - 12;
    console.log(coins);
28. 28.⚡ What number does this code print?
    let a = 10;
    let b = 5;
    console.log(a * b);
29. 29.⚡ What does this code show?
    let name = "Arjun";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Welcome, Arjun! (d) Arjun
30. 30.⚡ What number does this code print?
    let a = 44;
    let b = 26;
    console.log(a - b);
31. 31.⚡ What number does this code print?
    let a = 37;
    let b = 10;
    console.log(a + b);
32. 32.⚡ What number does this code print?
    let a = 50;
    let b = 35;
    console.log(a + b);
33. 33.⚡ What number does this code print?
    let a = 41;
    let b = 39;
    console.log(a - b);
34. 34.⚡ What number does this code print?
    let apples = 30;
    apples = apples + 2;
    apples = apples - 11;
    console.log(apples);
35. 35.⚡ What does this code show?
    let name = "Aman";
    alert("Well done, " + name + "!"); (a) Aman (b) Well done, Aman! (c) Well done, name! (d) name
36. 36.⚡ Which word makes a new variable? (a) let (b) put (c) make (d) give
37. 37.⚡ What does this code show?
    let name = "Meera";
    alert("Welcome, " + name + "!"); (a) name (b) Welcome, Meera! (c) Meera (d) Welcome, name!
38. 38.⚡ What number does this code print?
    let a = 53;
    let b = 14;
    console.log(a + b);
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 9;
    console.log(x + y); (a) 17 (b) Error (c) 89
40. 40.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) Welcome, Riya! (b) Welcome, name! (c) Riya (d) name

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