JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 927 · 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 = 58;
   let b = 18;
   console.log(a + b);
2. 2.⚡ What does this code print? (Look at the quotes!)
   let x = "4";
   let y = 3;
   console.log(x + y); (a) 7 (b) 43 (c) Error
3. 3.⚡ What number does this code print?
   let apples = 25;
   apples = apples + 8;
   apples = apples - 15;
   console.log(apples);
4. 4.⚡ What does this code print? (Look at the quotes!)
   let x = "3";
   let y = 3;
   console.log(x + y); (a) Error (b) 33 (c) 6
5. 5.⚡ What number does this code print?
   let a = 23;
   let b = 12;
   console.log(a + b);
6. 6.⚡ What does this code show?
   let name = "Aman";
   alert("Hello, " + name + "!"); (a) name (b) Hello, Aman! (c) Hello, name! (d) Aman
7. 7.⚡ What number does this code print?
   let a = 37;
   let b = 13;
   console.log(a - b);
8. 8.⚡ Which JavaScript word writes in the console? (a) for (b) if (c) console.log() (d) let
9. 9.⚡ What number does this code print?
   let a = 24;
   let b = 24;
   console.log(a + b);
10. 10.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) alert() (c) if (d) let
11. 11.⚡ What does alert() show? (a) a new tab (b) a picture (c) a pop-up box (d) a table
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 6;
    console.log(x + y); (a) Error (b) 96 (c) 15
13. 13.⚡ What number does this code print?
    let coins = 7;
    coins = coins + 11;
    coins = coins - 16;
    console.log(coins);
14. 14.⚡ Which JavaScript word makes a new variable? (a) let (b) for (c) console.log() (d) if
15. 15.⚡ What does JavaScript add to a web page? (a) only colours (b) actions and changes (c) the domain name (d) the page title
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 8;
    console.log(x + y); (a) Error (b) 98 (c) 17
17. 17.⚡ What does this code show?
    let name = "Meera";
    alert("Welcome, " + name + "!"); (a) Meera (b) Welcome, Meera! (c) Welcome, name! (d) name
18. 18.⚡ What number does this code print?
    let score = 5;
    score = score + 5;
    score = score - 3;
    console.log(score);
19. 19.⚡ What number does this code print?
    let score = 6;
    score = score + 16;
    score = score - 21;
    console.log(score);
20. 20.⚡ Which word makes a new variable? (a) put (b) give (c) make (d) let
21. 21.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 1;
    console.log(x + y); (a) 10 (b) Error (c) 91
22. 22.⚡ What number does this code print?
    let apples = 7;
    apples = apples + 9;
    apples = apples - 3;
    console.log(apples);
23. 23.⚡ What number does this code print?
    let score = 27;
    score = score + 3;
    score = score - 19;
    console.log(score);
24. 24.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 3;
    console.log(x + y); (a) Error (b) 5 (c) 23
25. 25.⚡ What number does this code print?
    let a = 4;
    let b = 6;
    console.log(a * b);
26. 26.⚡ What number does this code print?
    let a = 41;
    let b = 20;
    console.log(a - b);
27. 27.⚡ Where does console.log() show its output? (a) on the printer (b) in the address bar (c) on the title bar (d) in the console
28. 28.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!"); (a) name (b) Hello, name! (c) Hello, Riya! (d) Riya
29. 29.⚡ What number does this code print?
    let coins = 12;
    coins = coins + 17;
    coins = coins - 3;
    console.log(coins);
30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 5;
    console.log(x + y); (a) Error (b) 35 (c) 8
31. 31.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 6;
    console.log(x + y); (a) 56 (b) 11 (c) Error
32. 32.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .html (c) .jpg (d) .js
33. 33.⚡ 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
34. 34.⚡ What number does this code print?
    let coins = 16;
    coins = coins + 11;
    coins = coins - 9;
    console.log(coins);
35. 35.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hi, " + name + "!"); (a) name (b) Hi, Arjun! (c) Hi, name! (d) Arjun
36. 36.⚡ Which JavaScript word repeats code? (a) alert() (b) for (c) if (d) let
37. 37.⚡ What number does this code print?
    let books = 30;
    books = books + 2;
    books = books - 18;
    console.log(books);
38. 38.⚡ What number does this code print?
    let score = 11;
    score = score + 7;
    score = score - 8;
    console.log(score);
39. 39.⚡ What number does this code print?
    let a = 20;
    let b = 17;
    console.log(a + b);
40. 40.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) Zoya (c) name (d) Hello, Zoya!

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