JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 826 · 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 = "2";
   let y = 6;
   console.log(x + y); (a) 8 (b) Error (c) 26
2. 2.⚡ What number does this code print?
   let score = 27;
   score = score + 4;
   score = score - 12;
   console.log(score);
3. 3.⚡ What does this code show?
   let name = "Aman";
   alert("Well done, " + name + "!"); (a) Well done, Aman! (b) Aman (c) name (d) Well done, name!
4. 4.⚡ What number does this code print?
   let runs = 29;
   runs = runs + 4;
   runs = runs - 22;
   console.log(runs);
5. 5.⚡ Which JavaScript word writes in the console? (a) for (b) let (c) console.log() (d) alert()
6. 6.⚡ What number does this code print?
   let runs = 8;
   runs = runs + 8;
   runs = runs - 5;
   console.log(runs);
7. 7.⚡ What number does this code print?
   let marks = 8;
   marks = marks + 19;
   marks = marks - 9;
   console.log(marks);
8. 8.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <script> (c) <js> (d) <style>
9. 9.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .js (c) .css (d) .jpg
10. 10.⚡ Where does console.log() show its output? (a) on the printer (b) in the address bar (c) in the console (d) on the title bar
11. 11.⚡ What number does this code print?
    let a = 49;
    let b = 21;
    console.log(a + b);
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 9;
    console.log(x + y); (a) 39 (b) 12 (c) Error
13. 13.⚡ Which JavaScript word repeats code? (a) if (b) alert() (c) for (d) console.log()
14. 14.⚡ What number does this code print?
    let coins = 13;
    coins = coins + 3;
    coins = coins - 7;
    console.log(coins);
15. 15.⚡ What number does this code print?
    let a = 12;
    let b = 11;
    console.log(a * b);
16. 16.⚡ Which JavaScript word makes a new variable? (a) console.log() (b) alert() (c) let (d) if
17. 17.⚡ What number does this code print?
    let a = 40;
    let b = 21;
    console.log(a - b);
18. 18.⚡ What number does this code print?
    let a = 6;
    let b = 5;
    console.log(a * b);
19. 19.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) Hi, Riya! (b) name (c) Riya (d) Hi, name!
20. 20.⚡ What number does this code print?
    let a = 57;
    let b = 22;
    console.log(a + b);
21. 21.⚡ Which word makes a new variable? (a) make (b) give (c) let (d) put
22. 22.⚡ Which JavaScript word runs code when true? (a) if (b) alert() (c) let (d) for
23. 23.⚡ Which JavaScript word shows a pop-up box? (a) if (b) for (c) alert() (d) let
24. 24.⚡ What number does this code print?
    let a = 3;
    let b = 8;
    console.log(a * b);
25. 25.⚡ What number does this code print?
    let a = 10;
    let b = 2;
    console.log(a * b);
26. 26.⚡ What number does this code print?
    let apples = 17;
    apples = apples + 11;
    apples = apples - 27;
    console.log(apples);
27. 27.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!"); (a) Arjun (b) name (c) Hello, name! (d) Hello, Arjun!
28. 28.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 4;
    console.log(x + y); (a) 6 (b) Error (c) 24
29. 29.⚡ What does this code show?
    let name = "Aman";
    console.log("Well done, " + name + "!"); (a) Aman (b) name (c) Well done, name! (d) Well done, Aman!
30. 30.⚡ What number does this code print?
    let a = 40;
    let b = 12;
    console.log(a + b);
31. 31.⚡ What does alert() show? (a) a picture (b) a new tab (c) a pop-up box (d) a table
32. 32.⚡ What number does this code print?
    let a = 15;
    let b = 26;
    console.log(a + b);
33. 33.⚡ 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
34. 34.⚡ What number does this code print?
    let a = 4;
    let b = 4;
    console.log(a * b);
35. 35.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) Meera (b) Hello, name! (c) Hello, Meera! (d) name
36. 36.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) Riya (b) name (c) Welcome, name! (d) Welcome, Riya!
37. 37.⚡ What number does this code print?
    let a = 19;
    let b = 7;
    console.log(a - b);
38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 4;
    console.log(x + y); (a) 5 (b) 14 (c) Error
39. 39.⚡ What does JavaScript add to a web page? (a) the page title (b) the domain name (c) actions and changes (d) only colours
40. 40.⚡ What number does this code print?
    let a = 30;
    let b = 8;
    console.log(a - b);

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