JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 240 · 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 = 18;
   let b = 9;
   console.log(a - b);
2. 2.⚡ What number does this code print?
   let a = 55;
   let b = 30;
   console.log(a + b);
3. 3.⚡ What does this code show?
   let name = "Meera";
   alert("Hi, " + name + "!"); (a) Hi, name! (b) Meera (c) name (d) Hi, Meera!
4. 4.⚡ What does alert() show? (a) a pop-up box (b) a table (c) a picture (d) a new tab
5. 5.⚡ Which word makes a new variable? (a) put (b) give (c) make (d) let
6. 6.⚡ What number does this code print?
   let a = 57;
   let b = 12;
   console.log(a + b);
7. 7.⚡ Which JavaScript word writes in the console? (a) alert() (b) for (c) let (d) console.log()
8. 8.⚡ What number does this code print?
   let apples = 11;
   apples = apples + 4;
   apples = apples - 4;
   console.log(apples);
9. 9.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .css (c) .js (d) .html
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 6;
    console.log(x + y); (a) Error (b) 8 (c) 26
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 8;
    console.log(x + y); (a) 88 (b) Error (c) 16
12. 12.⚡ What number does this code print?
    let runs = 21;
    runs = runs + 6;
    runs = runs - 5;
    console.log(runs);
13. 13.⚡ Which JavaScript word shows a pop-up box? (a) alert() (b) let (c) for (d) console.log()
14. 14.⚡ What number does this code print?
    let a = 26;
    let b = 20;
    console.log(a - b);
15. 15.⚡ What number does this code print?
    let coins = 5;
    coins = coins + 15;
    coins = coins - 19;
    console.log(coins);
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 8;
    console.log(x + y); (a) 9 (b) Error (c) 18
17. 17.⚡ What does this code show?
    let name = "Riya";
    console.log("Hello, " + name + "!"); (a) name (b) Riya (c) Hello, Riya! (d) Hello, name!
18. 18.⚡ What number does this code print?
    let score = 12;
    score = score + 14;
    score = score - 10;
    console.log(score);
19. 19.⚡ Where does console.log() show its output? (a) on the printer (b) in the console (c) on the title bar (d) in the address bar
20. 20.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!"); (a) Hello, name! (b) name (c) Hello, Riya! (d) Riya
21. 21.⚡ What number does this code print?
    let runs = 23;
    runs = runs + 3;
    runs = runs - 7;
    console.log(runs);
22. 22.⚡ Which JavaScript word repeats code? (a) if (b) console.log() (c) let (d) for
23. 23.⚡ Which JavaScript word makes a new variable? (a) for (b) let (c) console.log() (d) if
24. 24.⚡ What does JavaScript add to a web page? (a) the domain name (b) actions and changes (c) the page title (d) only colours
25. 25.⚡ What number does this code print?
    let a = 29;
    let b = 40;
    console.log(a + b);
26. 26.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) Meera (c) name (d) Hello, Meera!
27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 8;
    console.log(x + y); (a) 17 (b) 98 (c) Error
28. 28.⚡ What number does this code print?
    let marks = 15;
    marks = marks + 3;
    marks = marks - 6;
    console.log(marks);
29. 29.⚡ Which JavaScript word runs code when true? (a) alert() (b) if (c) let (d) for
30. 30.⚡ What number does this code print?
    let coins = 15;
    coins = coins + 6;
    coins = coins - 20;
    console.log(coins);
31. 31.⚡ What number does this code print?
    let apples = 12;
    apples = apples + 13;
    apples = apples - 23;
    console.log(apples);
32. 32.⚡ What number does this code print?
    let a = 3;
    let b = 8;
    console.log(a * b);
33. 33.⚡ What number does this code print?
    let coins = 18;
    coins = coins + 14;
    coins = coins - 21;
    console.log(coins);
34. 34.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hi, " + name + "!"); (a) Hi, Kabir! (b) name (c) Kabir (d) Hi, name!
35. 35.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hello, " + name + "!"); (a) Hello, Zoya! (b) name (c) Zoya (d) Hello, name!
36. 36.⚡ What number does this code print?
    let books = 8;
    books = books + 19;
    books = books - 23;
    console.log(books);
37. 37.⚡ What does this code show?
    let name = "Aman";
    console.log("Hello, " + name + "!"); (a) Hello, Aman! (b) Hello, name! (c) Aman (d) name
38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 6;
    console.log(x + y); (a) 7 (b) Error (c) 16
39. 39.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Riya (d) Welcome, Riya!
40. 40.⚡ What number does this code print?
    let a = 50;
    let b = 32;
    console.log(a - b);

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