JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 729 · 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 = "1";
   let y = 2;
   console.log(x + y); (a) 3 (b) Error (c) 12
2. 2.⚡ What number does this code print?
   let a = 54;
   let b = 15;
   console.log(a + b);
3. 3.⚡ Which word makes a new variable? (a) let (b) give (c) put (d) make
4. 4.⚡ Which JavaScript word makes a new variable? (a) let (b) if (c) for (d) alert()
5. 5.⚡ What number does this code print?
   let marks = 12;
   marks = marks + 2;
   marks = marks - 13;
   console.log(marks);
6. 6.⚡ What does JavaScript add to a web page? (a) the domain name (b) only colours (c) actions and changes (d) the page title
7. 7.⚡ What number does this code print?
   let coins = 25;
   coins = coins + 16;
   coins = coins - 26;
   console.log(coins);
8. 8.⚡ 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
9. 9.⚡ What does this code show?
   let name = "Kabir";
   alert("Well done, " + name + "!"); (a) Well done, name! (b) Kabir (c) name (d) Well done, Kabir!
10. 10.⚡ What number does this code print?
    let marks = 13;
    marks = marks + 20;
    marks = marks - 25;
    console.log(marks);
11. 11.⚡ What number does this code print?
    let apples = 21;
    apples = apples + 5;
    apples = apples - 23;
    console.log(apples);
12. 12.⚡ What number does this code print?
    let a = 39;
    let b = 19;
    console.log(a - b);
13. 13.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <script> (c) <code> (d) <js>
14. 14.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 8;
    console.log(x + y); (a) 88 (b) 16 (c) Error
15. 15.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hi, " + name + "!"); (a) Zoya (b) name (c) Hi, Zoya! (d) Hi, name!
16. 16.⚡ What number does this code print?
    let books = 22;
    books = books + 6;
    books = books - 20;
    console.log(books);
17. 17.⚡ What number does this code print?
    let a = 3;
    let b = 6;
    console.log(a * b);
18. 18.⚡ What does this code show?
    let name = "Kabir";
    alert("Welcome, " + name + "!"); (a) name (b) Welcome, Kabir! (c) Kabir (d) Welcome, name!
19. 19.⚡ What number does this code print?
    let marks = 17;
    marks = marks + 14;
    marks = marks - 7;
    console.log(marks);
20. 20.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) alert() (c) for (d) if
21. 21.⚡ What number does this code print?
    let a = 6;
    let b = 2;
    console.log(a * b);
22. 22.⚡ What number does this code print?
    let a = 55;
    let b = 3;
    console.log(a + b);
23. 23.⚡ What number does this code print?
    let books = 26;
    books = books + 8;
    books = books - 16;
    console.log(books);
24. 24.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .css (c) .jpg (d) .html
25. 25.⚡ What does alert() show? (a) a pop-up box (b) a picture (c) a table (d) a new tab
26. 26.⚡ Which JavaScript word writes in the console? (a) console.log() (b) let (c) if (d) alert()
27. 27.⚡ Which JavaScript word repeats code? (a) alert() (b) if (c) console.log() (d) for
28. 28.⚡ What number does this code print?
    let a = 3;
    let b = 5;
    console.log(a * b);
29. 29.⚡ What number does this code print?
    let a = 7;
    let b = 11;
    console.log(a * b);
30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 6;
    console.log(x + y); (a) 10 (b) Error (c) 46
31. 31.⚡ Which JavaScript word runs code when true? (a) console.log() (b) alert() (c) let (d) if
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 2;
    console.log(x + y); (a) 72 (b) Error (c) 9
33. 33.⚡ Where does console.log() show its output? (a) in the console (b) on the title bar (c) on the printer (d) in the address bar
34. 34.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 6;
    console.log(x + y); (a) 36 (b) Error (c) 9
35. 35.⚡ What number does this code print?
    let a = 29;
    let b = 8;
    console.log(a + b);
36. 36.⚡ What number does this code print?
    let a = 29;
    let b = 20;
    console.log(a - b);
37. 37.⚡ What number does this code print?
    let a = 7;
    let b = 4;
    console.log(a * b);
38. 38.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) Riya (c) Welcome, Riya! (d) name
39. 39.⚡ What number does this code print?
    let a = 45;
    let b = 39;
    console.log(a + b);
40. 40.⚡ What does this code show?
    let name = "Kabir";
    console.log("Welcome, " + name + "!"); (a) name (b) Kabir (c) Welcome, Kabir! (d) Welcome, name!

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