JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 157 · 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 shows a pop-up box? (a) for (b) console.log() (c) alert() (d) let
2. 2.⚡ What does this code print? (Look at the quotes!)
   let x = "1";
   let y = 5;
   console.log(x + y); (a) 6 (b) Error (c) 15
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "7";
   let y = 2;
   console.log(x + y); (a) 9 (b) Error (c) 72
4. 4.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 1;
   console.log(x + y); (a) 3 (b) Error (c) 21
5. 5.⚡ Which JavaScript word runs code when true? (a) alert() (b) let (c) if (d) console.log()
6. 6.⚡ Which word makes a new variable? (a) put (b) let (c) make (d) give
7. 7.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <js> (c) <style> (d) <code>
8. 8.⚡ What number does this code print?
   let a = 36;
   let b = 3;
   console.log(a - b);
9. 9.⚡ Which JavaScript word makes a new variable? (a) for (b) alert() (c) console.log() (d) let
10. 10.⚡ What number does this code print?
    let a = 27;
    let b = 1;
    console.log(a + b);
11. 11.⚡ What does alert() show? (a) a new tab (b) a table (c) a picture (d) a pop-up box
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 1;
    console.log(x + y); (a) 51 (b) Error (c) 6
13. 13.⚡ What number does this code print?
    let a = 53;
    let b = 12;
    console.log(a + b);
14. 14.⚡ What does this code show?
    let name = "Arjun";
    alert("Hi, " + name + "!"); (a) Arjun (b) Hi, Arjun! (c) Hi, name! (d) name
15. 15.⚡ What number does this code print?
    let a = 46;
    let b = 15;
    console.log(a + b);
16. 16.⚡ Which JavaScript word writes in the console? (a) console.log() (b) let (c) alert() (d) if
17. 17.⚡ What number does this code print?
    let a = 20;
    let b = 35;
    console.log(a + b);
18. 18.⚡ What does JavaScript add to a web page? (a) the page title (b) the domain name (c) only colours (d) actions and changes
19. 19.⚡ Which JavaScript word repeats code? (a) console.log() (b) alert() (c) for (d) let
20. 20.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 7;
    console.log(x + y); (a) Error (b) 97 (c) 16
21. 21.⚡ What number does this code print?
    let coins = 23;
    coins = coins + 15;
    coins = coins - 19;
    console.log(coins);
22. 22.⚡ What number does this code print?
    let marks = 18;
    marks = marks + 11;
    marks = marks - 4;
    console.log(marks);
23. 23.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) Hello, Zoya! (c) Zoya (d) name
24. 24.⚡ What number does this code print?
    let a = 9;
    let b = 12;
    console.log(a + b);
25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 5;
    console.log(x + y); (a) 65 (b) Error (c) 11
26. 26.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 8;
    console.log(x + y); (a) 14 (b) Error (c) 68
27. 27.⚡ What number does this code print?
    let a = 24;
    let b = 23;
    console.log(a + b);
28. 28.⚡ What number does this code print?
    let a = 60;
    let b = 35;
    console.log(a - b);
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 1;
    console.log(x + y); (a) 31 (b) 4 (c) Error
30. 30.⚡ What does this code show?
    let name = "Meera";
    alert("Hi, " + name + "!"); (a) Hi, Meera! (b) Meera (c) name (d) Hi, name!
31. 31.⚡ What number does this code print?
    let coins = 22;
    coins = coins + 14;
    coins = coins - 1;
    console.log(coins);
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 8;
    console.log(x + y); (a) 17 (b) Error (c) 98
33. 33.⚡ What number does this code print?
    let score = 9;
    score = score + 16;
    score = score - 5;
    console.log(score);
34. 34.⚡ Where does console.log() show its output? (a) on the title bar (b) in the console (c) on the printer (d) in the address bar
35. 35.⚡ What number does this code print?
    let marks = 29;
    marks = marks + 14;
    marks = marks - 7;
    console.log(marks);
36. 36.⚡ What number does this code print?
    let books = 7;
    books = books + 20;
    books = books - 3;
    console.log(books);
37. 37.⚡ What number does this code print?
    let a = 42;
    let b = 12;
    console.log(a - b);
38. 38.⚡ What number does this code print?
    let runs = 19;
    runs = runs + 6;
    runs = runs - 20;
    console.log(runs);
39. 39.⚡ What number does this code print?
    let books = 5;
    books = books + 7;
    books = books - 3;
    console.log(books);
40. 40.⚡ What number does this code print?
    let a = 8;
    let b = 4;
    console.log(a * b);

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