JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 488 · 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 show?
   let name = "Arjun";
   console.log("Hello, " + name + "!"); (a) name (b) Arjun (c) Hello, name! (d) Hello, Arjun!
2. 2.⚡ What number does this code print?
   let runs = 23;
   runs = runs + 6;
   runs = runs - 21;
   console.log(runs);
3. 3.⚡ What does JavaScript add to a web page? (a) actions and changes (b) only colours (c) the page title (d) the domain name
4. 4.⚡ What does this code show?
   let name = "Meera";
   console.log("Welcome, " + name + "!"); (a) name (b) Welcome, name! (c) Meera (d) Welcome, Meera!
5. 5.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .html (c) .css (d) .jpg
6. 6.⚡ Which JavaScript word shows a pop-up box? (a) for (b) alert() (c) if (d) let
7. 7.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 4;
   console.log(x + y); (a) 9 (b) Error (c) 54
8. 8.⚡ What number does this code print?
   let coins = 28;
   coins = coins + 18;
   coins = coins - 3;
   console.log(coins);
9. 9.⚡ Which JavaScript word writes in the console? (a) console.log() (b) let (c) alert() (d) for
10. 10.⚡ Which JavaScript word runs code when true? (a) alert() (b) if (c) console.log() (d) let
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 2;
    console.log(x + y); (a) 8 (b) Error (c) 62
12. 12.⚡ Which JavaScript word makes a new variable? (a) for (b) if (c) let (d) console.log()
13. 13.⚡ What does this code show?
    let name = "Arjun";
    alert("Welcome, " + name + "!"); (a) name (b) Welcome, Arjun! (c) Arjun (d) Welcome, name!
14. 14.⚡ What number does this code print?
    let a = 5;
    let b = 7;
    console.log(a * b);
15. 15.⚡ Which JavaScript word repeats code? (a) for (b) console.log() (c) if (d) alert()
16. 16.⚡ What number does this code print?
    let apples = 14;
    apples = apples + 7;
    apples = apples - 15;
    console.log(apples);
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 1;
    console.log(x + y); (a) 7 (b) 61 (c) Error
18. 18.⚡ Which word makes a new variable? (a) put (b) make (c) give (d) let
19. 19.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) Hello, Meera! (c) name (d) Meera
20. 20.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 9;
    console.log(x + y); (a) 17 (b) 89 (c) Error
21. 21.⚡ What does alert() show? (a) a picture (b) a new tab (c) a table (d) a pop-up box
22. 22.⚡ Where does console.log() show its output? (a) in the console (b) on the printer (c) in the address bar (d) on the title bar
23. 23.⚡ What number does this code print?
    let a = 23;
    let b = 20;
    console.log(a + b);
24. 24.⚡ What number does this code print?
    let a = 11;
    let b = 6;
    console.log(a - b);
25. 25.⚡ What number does this code print?
    let apples = 15;
    apples = apples + 2;
    apples = apples - 7;
    console.log(apples);
26. 26.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 3;
    console.log(x + y); (a) 4 (b) 13 (c) Error
27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 6;
    console.log(x + y); (a) Error (b) 36 (c) 9
28. 28.⚡ What number does this code print?
    let apples = 20;
    apples = apples + 8;
    apples = apples - 28;
    console.log(apples);
29. 29.⚡ 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
30. 30.⚡ What number does this code print?
    let books = 23;
    books = books + 5;
    books = books - 7;
    console.log(books);
31. 31.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 2;
    console.log(x + y); (a) 3 (b) 12 (c) Error
32. 32.⚡ What number does this code print?
    let marks = 28;
    marks = marks + 9;
    marks = marks - 12;
    console.log(marks);
33. 33.⚡ What number does this code print?
    let marks = 22;
    marks = marks + 17;
    marks = marks - 18;
    console.log(marks);
34. 34.⚡ What number does this code print?
    let a = 10;
    let b = 5;
    console.log(a * b);
35. 35.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!"); (a) name (b) Riya (c) Hello, Riya! (d) Hello, name!
36. 36.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) Kabir (c) name (d) Hello, Kabir!
37. 37.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 2;
    console.log(x + y); (a) 92 (b) 11 (c) Error
38. 38.⚡ What number does this code print?
    let score = 21;
    score = score + 17;
    score = score - 23;
    console.log(score);
39. 39.⚡ What number does this code print?
    let coins = 11;
    coins = coins + 4;
    coins = coins - 5;
    console.log(coins);
40. 40.⚡ What number does this code print?
    let coins = 6;
    coins = coins + 2;
    coins = coins - 7;
    console.log(coins);

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