JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 537 · 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 does this code print? (Look at the quotes!)
   let x = "6";
   let y = 7;
   console.log(x + y); (a) 67 (b) Error (c) 13
2. 2.⚡ What does this code print? (Look at the quotes!)
   let x = "7";
   let y = 3;
   console.log(x + y); (a) Error (b) 73 (c) 10
3. 3.⚡ What number does this code print?
   let a = 7;
   let b = 3;
   console.log(a * b);
4. 4.⚡ What number does this code print?
   let score = 11;
   score = score + 2;
   score = score - 5;
   console.log(score);
5. 5.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 2;
   console.log(x + y); (a) 22 (b) 4 (c) Error
6. 6.⚡ Which word makes a new variable? (a) put (b) let (c) give (d) make
7. 7.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 9;
   console.log(x + y); (a) Error (b) 29 (c) 11
8. 8.⚡ Which JavaScript word repeats code? (a) alert() (b) for (c) console.log() (d) if
9. 9.⚡ Where does console.log() show its output? (a) on the printer (b) in the address bar (c) on the title bar (d) in the console
10. 10.⚡ What number does this code print?
    let a = 24;
    let b = 22;
    console.log(a - b);
11. 11.⚡ Which JavaScript word writes in the console? (a) console.log() (b) for (c) let (d) alert()
12. 12.⚡ What does this code show?
    let name = "Zoya";
    alert("Welcome, " + name + "!"); (a) name (b) Welcome, name! (c) Welcome, Zoya! (d) Zoya
13. 13.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 5;
    console.log(x + y); (a) 13 (b) 85 (c) Error
14. 14.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) Riya (c) Welcome, Riya! (d) name
15. 15.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 2;
    console.log(x + y); (a) 9 (b) 72 (c) Error
16. 16.⚡ What number does this code print?
    let a = 7;
    let b = 10;
    console.log(a * b);
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 8;
    console.log(x + y); (a) 9 (b) 18 (c) Error
18. 18.⚡ What number does this code print?
    let score = 9;
    score = score + 10;
    score = score - 5;
    console.log(score);
19. 19.⚡ What number does this code print?
    let score = 17;
    score = score + 19;
    score = score - 36;
    console.log(score);
20. 20.⚡ Which JavaScript word shows a pop-up box? (a) if (b) alert() (c) for (d) console.log()
21. 21.⚡ What number does this code print?
    let coins = 27;
    coins = coins + 7;
    coins = coins - 21;
    console.log(coins);
22. 22.⚡ Which JavaScript word runs code when true? (a) console.log() (b) if (c) for (d) let
23. 23.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <style> (c) <js> (d) <code>
24. 24.⚡ What does alert() show? (a) a table (b) a new tab (c) a picture (d) a pop-up box
25. 25.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) name (c) Hello, Meera! (d) Meera
26. 26.⚡ What number does this code print?
    let a = 34;
    let b = 13;
    console.log(a - b);
27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 4;
    console.log(x + y); (a) 12 (b) Error (c) 84
28. 28.⚡ What number does this code print?
    let a = 38;
    let b = 3;
    console.log(a + b);
29. 29.⚡ What number does this code print?
    let marks = 10;
    marks = marks + 19;
    marks = marks - 7;
    console.log(marks);
30. 30.⚡ What does this code show?
    let name = "Arjun";
    console.log("Welcome, " + name + "!"); (a) Welcome, Arjun! (b) Welcome, name! (c) Arjun (d) name
31. 31.⚡ What does this code show?
    let name = "Meera";
    alert("Welcome, " + name + "!"); (a) Welcome, Meera! (b) Meera (c) name (d) Welcome, name!
32. 32.⚡ What number does this code print?
    let a = 22;
    let b = 8;
    console.log(a + b);
33. 33.⚡ What does this code show?
    let name = "Zoya";
    console.log("Welcome, " + name + "!"); (a) name (b) Welcome, Zoya! (c) Welcome, name! (d) Zoya
34. 34.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .js (c) .css (d) .html
35. 35.⚡ What number does this code print?
    let books = 18;
    books = books + 5;
    books = books - 5;
    console.log(books);
36. 36.⚡ What does JavaScript add to a web page? (a) the page title (b) actions and changes (c) only colours (d) the domain name
37. 37.⚡ What number does this code print?
    let a = 54;
    let b = 9;
    console.log(a - b);
38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 7;
    console.log(x + y); (a) Error (b) 10 (c) 37
39. 39.⚡ What number does this code print?
    let score = 28;
    score = score + 15;
    score = score - 35;
    console.log(score);
40. 40.⚡ What number does this code print?
    let a = 47;
    let b = 14;
    console.log(a + b);

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