JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 203 · 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 = 9;
   let b = 11;
   console.log(a + b);
2. 2.⚡ What number does this code print?
   let coins = 14;
   coins = coins + 4;
   coins = coins - 2;
   console.log(coins);
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 5;
   console.log(x + y); (a) Error (b) 7 (c) 25
4. 4.⚡ What does alert() show? (a) a pop-up box (b) a picture (c) a new tab (d) a table
5. 5.⚡ What number does this code print?
   let a = 7;
   let b = 3;
   console.log(a * b);
6. 6.⚡ What number does this code print?
   let a = 22;
   let b = 20;
   console.log(a - b);
7. 7.⚡ What number does this code print?
   let a = 6;
   let b = 27;
   console.log(a + b);
8. 8.⚡ Which JavaScript word repeats code? (a) for (b) let (c) alert() (d) console.log()
9. 9.⚡ What number does this code print?
   let a = 28;
   let b = 26;
   console.log(a + b);
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 4;
    console.log(x + y); (a) 54 (b) 9 (c) Error
11. 11.⚡ What number does this code print?
    let books = 10;
    books = books + 6;
    books = books - 15;
    console.log(books);
12. 12.⚡ What number does this code print?
    let coins = 27;
    coins = coins + 5;
    coins = coins - 5;
    console.log(coins);
13. 13.⚡ What number does this code print?
    let a = 30;
    let b = 19;
    console.log(a + b);
14. 14.⚡ What does this code show?
    let name = "Kabir";
    alert("Hello, " + name + "!"); (a) Hello, name! (b) name (c) Hello, Kabir! (d) Kabir
15. 15.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 1;
    console.log(x + y); (a) Error (b) 9 (c) 81
16. 16.⚡ What number does this code print?
    let coins = 7;
    coins = coins + 9;
    coins = coins - 7;
    console.log(coins);
17. 17.⚡ What number does this code print?
    let marks = 14;
    marks = marks + 3;
    marks = marks - 16;
    console.log(marks);
18. 18.⚡ Which JavaScript word writes in the console? (a) console.log() (b) let (c) for (d) alert()
19. 19.⚡ What does JavaScript add to a web page? (a) the page title (b) actions and changes (c) the domain name (d) only colours
20. 20.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .css (c) .html (d) .jpg
21. 21.⚡ What does this code show?
    let name = "Kabir";
    alert("Welcome, " + name + "!"); (a) Kabir (b) Welcome, Kabir! (c) name (d) Welcome, name!
22. 22.⚡ What number does this code print?
    let a = 8;
    let b = 4;
    console.log(a * b);
23. 23.⚡ What does this code show?
    let name = "Zoya";
    console.log("Well done, " + name + "!"); (a) Well done, name! (b) Well done, Zoya! (c) Zoya (d) name
24. 24.⚡ What number does this code print?
    let a = 49;
    let b = 28;
    console.log(a - b);
25. 25.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 3;
    console.log(x + y); (a) 6 (b) Error (c) 33
26. 26.⚡ What number does this code print?
    let score = 23;
    score = score + 10;
    score = score - 12;
    console.log(score);
27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 3;
    console.log(x + y); (a) 9 (b) 63 (c) Error
28. 28.⚡ What does this code show?
    let name = "Meera";
    console.log("Well done, " + name + "!"); (a) Well done, Meera! (b) Well done, name! (c) name (d) Meera
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 4;
    console.log(x + y); (a) 12 (b) 84 (c) Error
30. 30.⚡ What number does this code print?
    let marks = 26;
    marks = marks + 5;
    marks = marks - 10;
    console.log(marks);
31. 31.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 6;
    console.log(x + y); (a) Error (b) 10 (c) 46
32. 32.⚡ Which JavaScript word shows a pop-up box? (a) let (b) console.log() (c) for (d) alert()
33. 33.⚡ What does this code show?
    let name = "Aman";
    alert("Welcome, " + name + "!"); (a) Aman (b) name (c) Welcome, Aman! (d) Welcome, name!
34. 34.⚡ What number does this code print?
    let coins = 26;
    coins = coins + 2;
    coins = coins - 10;
    console.log(coins);
35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 6;
    console.log(x + y); (a) 13 (b) Error (c) 76
36. 36.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hi, " + name + "!"); (a) Kabir (b) name (c) Hi, Kabir! (d) Hi, name!
37. 37.⚡ What number does this code print?
    let a = 21;
    let b = 6;
    console.log(a - b);
38. 38.⚡ What number does this code print?
    let score = 27;
    score = score + 18;
    score = score - 20;
    console.log(score);
39. 39.⚡ What number does this code print?
    let a = 11;
    let b = 3;
    console.log(a * b);
40. 40.⚡ What number does this code print?
    let marks = 15;
    marks = marks + 13;
    marks = marks - 28;
    console.log(marks);

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