JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 103 · 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 = 12;
   let b = 3;
   console.log(a * b);
2. 2.⚡ What does this code show?
   let name = "Kabir";
   console.log("Hi, " + name + "!"); (a) Hi, Kabir! (b) Kabir (c) Hi, name! (d) name
3. 3.⚡ What number does this code print?
   let runs = 29;
   runs = runs + 17;
   runs = runs - 5;
   console.log(runs);
4. 4.⚡ What number does this code print?
   let score = 15;
   score = score + 5;
   score = score - 19;
   console.log(score);
5. 5.⚡ What number does this code print?
   let a = 22;
   let b = 16;
   console.log(a - b);
6. 6.⚡ What does this code print? (Look at the quotes!)
   let x = "8";
   let y = 1;
   console.log(x + y); (a) 9 (b) Error (c) 81
7. 7.⚡ What number does this code print?
   let a = 60;
   let b = 1;
   console.log(a - b);
8. 8.⚡ Which JavaScript word repeats code? (a) alert() (b) for (c) if (d) console.log()
9. 9.⚡ Which JavaScript word runs code when true? (a) console.log() (b) alert() (c) for (d) if
10. 10.⚡ What does alert() show? (a) a picture (b) a new tab (c) a pop-up box (d) a table
11. 11.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .css (c) .js (d) .html
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 9;
    console.log(x + y); (a) Error (b) 11 (c) 29
13. 13.⚡ What number does this code print?
    let a = 42;
    let b = 29;
    console.log(a - b);
14. 14.⚡ What number does this code print?
    let marks = 11;
    marks = marks + 7;
    marks = marks - 1;
    console.log(marks);
15. 15.⚡ 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
16. 16.⚡ What number does this code print?
    let a = 11;
    let b = 3;
    console.log(a * b);
17. 17.⚡ What number does this code print?
    let marks = 26;
    marks = marks + 9;
    marks = marks - 15;
    console.log(marks);
18. 18.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 1;
    console.log(x + y); (a) 91 (b) Error (c) 10
19. 19.⚡ What number does this code print?
    let runs = 23;
    runs = runs + 7;
    runs = runs - 1;
    console.log(runs);
20. 20.⚡ Which word makes a new variable? (a) give (b) put (c) let (d) make
21. 21.⚡ What number does this code print?
    let a = 47;
    let b = 3;
    console.log(a - b);
22. 22.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 8;
    console.log(x + y); (a) 13 (b) 58 (c) Error
23. 23.⚡ What number does this code print?
    let a = 23;
    let b = 34;
    console.log(a + b);
24. 24.⚡ What number does this code print?
    let a = 21;
    let b = 9;
    console.log(a + b);
25. 25.⚡ What does JavaScript add to a web page? (a) only colours (b) actions and changes (c) the page title (d) the domain name
26. 26.⚡ What does this code show?
    let name = "Riya";
    console.log("Hi, " + name + "!"); (a) Hi, Riya! (b) Hi, name! (c) Riya (d) name
27. 27.⚡ What number does this code print?
    let books = 23;
    books = books + 6;
    books = books - 4;
    console.log(books);
28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 7;
    console.log(x + y); (a) Error (b) 37 (c) 10
29. 29.⚡ What number does this code print?
    let marks = 30;
    marks = marks + 13;
    marks = marks - 6;
    console.log(marks);
30. 30.⚡ Which JavaScript word writes in the console? (a) for (b) console.log() (c) let (d) alert()
31. 31.⚡ Which JavaScript word makes a new variable? (a) if (b) let (c) for (d) alert()
32. 32.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) let (c) alert() (d) for
33. 33.⚡ What number does this code print?
    let a = 6;
    let b = 8;
    console.log(a * b);
34. 34.⚡ Which tag holds JavaScript in a page? (a) <js> (b) <code> (c) <script> (d) <style>
35. 35.⚡ What number does this code print?
    let apples = 14;
    apples = apples + 14;
    apples = apples - 12;
    console.log(apples);
36. 36.⚡ Where does console.log() show its output? (a) in the address bar (b) on the printer (c) in the console (d) on the title bar
37. 37.⚡ What number does this code print?
    let runs = 24;
    runs = runs + 7;
    runs = runs - 29;
    console.log(runs);
38. 38.⚡ What does this code show?
    let name = "Meera";
    console.log("Well done, " + name + "!"); (a) Well done, Meera! (b) Meera (c) name (d) Well done, name!
39. 39.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hi, " + name + "!"); (a) Hi, name! (b) Hi, Arjun! (c) Arjun (d) name
40. 40.⚡ What number does this code print?
    let a = 12;
    let b = 27;
    console.log(a + b);

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