JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 736 · 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 tag holds JavaScript in a page? (a) <style> (b) <code> (c) <js> (d) <script>
2. 2.⚡ Which JavaScript word runs code when true? (a) console.log() (b) alert() (c) if (d) let
3. 3.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .css (c) .jpg (d) .html
4. 4.⚡ What number does this code print?
   let a = 3;
   let b = 4;
   console.log(a * b);
5. 5.⚡ What does this code print? (Look at the quotes!)
   let x = "1";
   let y = 4;
   console.log(x + y); (a) 5 (b) Error (c) 14
6. 6.⚡ What number does this code print?
   let score = 6;
   score = score + 6;
   score = score - 3;
   console.log(score);
7. 7.⚡ What number does this code print?
   let a = 40;
   let b = 16;
   console.log(a - b);
8. 8.⚡ Which JavaScript word writes in the console? (a) if (b) console.log() (c) for (d) alert()
9. 9.⚡ What number does this code print?
   let a = 32;
   let b = 38;
   console.log(a + b);
10. 10.⚡ What number does this code print?
    let a = 31;
    let b = 5;
    console.log(a - b);
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 7;
    console.log(x + y); (a) 14 (b) Error (c) 77
12. 12.⚡ What number does this code print?
    let marks = 25;
    marks = marks + 14;
    marks = marks - 9;
    console.log(marks);
13. 13.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 6;
    console.log(x + y); (a) 96 (b) 15 (c) Error
14. 14.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) for (c) alert() (d) if
15. 15.⚡ Which JavaScript word repeats code? (a) for (b) console.log() (c) alert() (d) let
16. 16.⚡ What number does this code print?
    let score = 29;
    score = score + 18;
    score = score - 12;
    console.log(score);
17. 17.⚡ What number does this code print?
    let a = 4;
    let b = 4;
    console.log(a * b);
18. 18.⚡ What number does this code print?
    let a = 51;
    let b = 25;
    console.log(a + b);
19. 19.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) Hello, Meera! (b) Hello, name! (c) name (d) Meera
20. 20.⚡ What number does this code print?
    let a = 5;
    let b = 1;
    console.log(a + b);
21. 21.⚡ Which JavaScript word makes a new variable? (a) for (b) if (c) let (d) alert()
22. 22.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hi, " + name + "!"); (a) name (b) Kabir (c) Hi, name! (d) Hi, Kabir!
23. 23.⚡ Which word makes a new variable? (a) give (b) put (c) let (d) make
24. 24.⚡ What number does this code print?
    let a = 42;
    let b = 19;
    console.log(a + b);
25. 25.⚡ What number does this code print?
    let a = 5;
    let b = 3;
    console.log(a * b);
26. 26.⚡ What number does this code print?
    let coins = 19;
    coins = coins + 18;
    coins = coins - 36;
    console.log(coins);
27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 2;
    console.log(x + y); (a) Error (b) 52 (c) 7
28. 28.⚡ What number does this code print?
    let a = 42;
    let b = 13;
    console.log(a - b);
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 8;
    console.log(x + y); (a) 17 (b) 98 (c) Error
30. 30.⚡ What does JavaScript add to a web page? (a) the page title (b) the domain name (c) only colours (d) actions and changes
31. 31.⚡ What number does this code print?
    let marks = 10;
    marks = marks + 17;
    marks = marks - 9;
    console.log(marks);
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 7;
    console.log(x + y); (a) Error (b) 16 (c) 97
33. 33.⚡ What does alert() show? (a) a new tab (b) a pop-up box (c) a table (d) a picture
34. 34.⚡ What number does this code print?
    let books = 15;
    books = books + 3;
    books = books - 6;
    console.log(books);
35. 35.⚡ What number does this code print?
    let a = 4;
    let b = 6;
    console.log(a * b);
36. 36.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 2;
    console.log(x + y); (a) 22 (b) Error (c) 4
37. 37.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 4;
    console.log(x + y); (a) 11 (b) Error (c) 74
38. 38.⚡ What does this code show?
    let name = "Zoya";
    alert("Hi, " + name + "!"); (a) Zoya (b) Hi, name! (c) Hi, Zoya! (d) name
39. 39.⚡ What number does this code print?
    let score = 13;
    score = score + 5;
    score = score - 1;
    console.log(score);
40. 40.⚡ What number does this code print?
    let apples = 7;
    apples = apples + 13;
    apples = apples - 4;
    console.log(apples);

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