JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 634 · 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 JavaScript word makes a new variable? (a) let (b) console.log() (c) for (d) if
2. 2.⚡ What does alert() show? (a) a pop-up box (b) a table (c) a picture (d) a new tab
3. 3.⚡ What number does this code print?
   let score = 25;
   score = score + 12;
   score = score - 30;
   console.log(score);
4. 4.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 5;
   console.log(x + y); (a) 10 (b) Error (c) 55
5. 5.⚡ What number does this code print?
   let a = 6;
   let b = 7;
   console.log(a + b);
6. 6.⚡ Where does console.log() show its output? (a) on the printer (b) in the console (c) in the address bar (d) on the title bar
7. 7.⚡ Which JavaScript word shows a pop-up box? (a) if (b) let (c) for (d) alert()
8. 8.⚡ What number does this code print?
   let a = 28;
   let b = 22;
   console.log(a - b);
9. 9.⚡ What does this code show?
   let name = "Aman";
   alert("Hi, " + name + "!"); (a) Aman (b) Hi, Aman! (c) Hi, name! (d) name
10. 10.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <style> (c) <script> (d) <js>
11. 11.⚡ What does JavaScript add to a web page? (a) the page title (b) the domain name (c) actions and changes (d) only colours
12. 12.⚡ What number does this code print?
    let marks = 16;
    marks = marks + 5;
    marks = marks - 13;
    console.log(marks);
13. 13.⚡ What does this code show?
    let name = "Kabir";
    alert("Hi, " + name + "!"); (a) Kabir (b) Hi, name! (c) name (d) Hi, Kabir!
14. 14.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 4;
    console.log(x + y); (a) 64 (b) Error (c) 10
15. 15.⚡ What does this code show?
    let name = "Zoya";
    alert("Well done, " + name + "!"); (a) Well done, name! (b) Zoya (c) Well done, Zoya! (d) name
16. 16.⚡ What number does this code print?
    let a = 34;
    let b = 19;
    console.log(a - b);
17. 17.⚡ What number does this code print?
    let coins = 5;
    coins = coins + 5;
    coins = coins - 6;
    console.log(coins);
18. 18.⚡ What number does this code print?
    let a = 10;
    let b = 25;
    console.log(a + b);
19. 19.⚡ What number does this code print?
    let apples = 16;
    apples = apples + 16;
    apples = apples - 9;
    console.log(apples);
20. 20.⚡ What number does this code print?
    let runs = 7;
    runs = runs + 6;
    runs = runs - 9;
    console.log(runs);
21. 21.⚡ What number does this code print?
    let a = 11;
    let b = 4;
    console.log(a + b);
22. 22.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 5;
    console.log(x + y); (a) 11 (b) Error (c) 65
23. 23.⚡ What number does this code print?
    let a = 4;
    let b = 4;
    console.log(a * b);
24. 24.⚡ What does this code show?
    let name = "Zoya";
    alert("Hello, " + name + "!"); (a) Hello, Zoya! (b) Hello, name! (c) name (d) Zoya
25. 25.⚡ Which word makes a new variable? (a) let (b) make (c) put (d) give
26. 26.⚡ What number does this code print?
    let a = 18;
    let b = 9;
    console.log(a - b);
27. 27.⚡ What number does this code print?
    let coins = 30;
    coins = coins + 9;
    coins = coins - 9;
    console.log(coins);
28. 28.⚡ What does this code show?
    let name = "Aman";
    console.log("Well done, " + name + "!"); (a) Aman (b) Well done, Aman! (c) Well done, name! (d) name
29. 29.⚡ Which JavaScript word writes in the console? (a) alert() (b) if (c) console.log() (d) for
30. 30.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) Hi, Riya! (b) Hi, name! (c) name (d) Riya
31. 31.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .html (c) .jpg (d) .css
32. 32.⚡ What number does this code print?
    let marks = 16;
    marks = marks + 2;
    marks = marks - 11;
    console.log(marks);
33. 33.⚡ What number does this code print?
    let coins = 13;
    coins = coins + 10;
    coins = coins - 23;
    console.log(coins);
34. 34.⚡ Which JavaScript word repeats code? (a) if (b) for (c) console.log() (d) let
35. 35.⚡ What number does this code print?
    let score = 6;
    score = score + 3;
    score = score - 2;
    console.log(score);
36. 36.⚡ What does this code show?
    let name = "Aman";
    alert("Welcome, " + name + "!"); (a) Welcome, Aman! (b) Aman (c) Welcome, name! (d) name
37. 37.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 3;
    console.log(x + y); (a) 7 (b) Error (c) 43
38. 38.⚡ What number does this code print?
    let books = 29;
    books = books + 20;
    books = books - 20;
    console.log(books);
39. 39.⚡ What does this code show?
    let name = "Meera";
    alert("Hello, " + name + "!"); (a) Hello, Meera! (b) Hello, name! (c) Meera (d) name
40. 40.⚡ What does this code show?
    let name = "Aman";
    alert("Hello, " + name + "!"); (a) Hello, Aman! (b) name (c) Aman (d) Hello, name!

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