JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 221 · 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 tag holds JavaScript in a page? (a) <js> (b) <style> (c) <code> (d) <script>
2. 2.⚡ 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
3. 3.⚡ Where does console.log() show its output? (a) in the console (b) on the title bar (c) on the printer (d) in the address bar
4. 4.⚡ What does this code print? (Look at the quotes!)
   let x = "6";
   let y = 7;
   console.log(x + y); (a) Error (b) 13 (c) 67
5. 5.⚡ Which JavaScript word writes in the console? (a) let (b) if (c) console.log() (d) for
6. 6.⚡ What number does this code print?
   let a = 16;
   let b = 8;
   console.log(a - b);
7. 7.⚡ What does this code print? (Look at the quotes!)
   let x = "5";
   let y = 9;
   console.log(x + y); (a) Error (b) 59 (c) 14
8. 8.⚡ What does this code print? (Look at the quotes!)
   let x = "7";
   let y = 3;
   console.log(x + y); (a) 10 (b) 73 (c) Error
9. 9.⚡ What number does this code print?
   let runs = 9;
   runs = runs + 8;
   runs = runs - 2;
   console.log(runs);
10. 10.⚡ What number does this code print?
    let a = 43;
    let b = 30;
    console.log(a - b);
11. 11.⚡ What number does this code print?
    let a = 27;
    let b = 12;
    console.log(a - b);
12. 12.⚡ What number does this code print?
    let coins = 23;
    coins = coins + 10;
    coins = coins - 18;
    console.log(coins);
13. 13.⚡ What number does this code print?
    let score = 23;
    score = score + 12;
    score = score - 4;
    console.log(score);
14. 14.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .js (c) .css (d) .jpg
15. 15.⚡ What number does this code print?
    let apples = 9;
    apples = apples + 17;
    apples = apples - 21;
    console.log(apples);
16. 16.⚡ Which JavaScript word repeats code? (a) if (b) for (c) alert() (d) let
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 2;
    console.log(x + y); (a) Error (b) 92 (c) 11
18. 18.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 3;
    console.log(x + y); (a) 12 (b) Error (c) 93
19. 19.⚡ Which JavaScript word shows a pop-up box? (a) if (b) let (c) alert() (d) console.log()
20. 20.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 4;
    console.log(x + y); (a) Error (b) 12 (c) 84
21. 21.⚡ What does this code show?
    let name = "Kabir";
    alert("Well done, " + name + "!"); (a) Well done, name! (b) name (c) Kabir (d) Well done, Kabir!
22. 22.⚡ Which word makes a new variable? (a) let (b) put (c) give (d) make
23. 23.⚡ What number does this code print?
    let coins = 10;
    coins = coins + 2;
    coins = coins - 7;
    console.log(coins);
24. 24.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hi, " + name + "!"); (a) Hi, Kabir! (b) Kabir (c) name (d) Hi, name!
25. 25.⚡ What number does this code print?
    let coins = 24;
    coins = coins + 15;
    coins = coins - 35;
    console.log(coins);
26. 26.⚡ Which JavaScript word makes a new variable? (a) let (b) console.log() (c) for (d) if
27. 27.⚡ What does this code show?
    let name = "Riya";
    console.log("Well done, " + name + "!"); (a) name (b) Well done, name! (c) Well done, Riya! (d) Riya
28. 28.⚡ What does this code show?
    let name = "Zoya";
    alert("Welcome, " + name + "!"); (a) Welcome, Zoya! (b) name (c) Welcome, name! (d) Zoya
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 6;
    console.log(x + y); (a) 9 (b) Error (c) 36
30. 30.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!"); (a) name (b) Riya (c) Hello, name! (d) Hello, Riya!
31. 31.⚡ What does alert() show? (a) a new tab (b) a picture (c) a pop-up box (d) a table
32. 32.⚡ What does this code show?
    let name = "Meera";
    alert("Welcome, " + name + "!"); (a) name (b) Meera (c) Welcome, name! (d) Welcome, Meera!
33. 33.⚡ What number does this code print?
    let a = 26;
    let b = 21;
    console.log(a - b);
34. 34.⚡ What number does this code print?
    let a = 12;
    let b = 3;
    console.log(a * b);
35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 1;
    console.log(x + y); (a) 8 (b) Error (c) 71
36. 36.⚡ What number does this code print?
    let books = 9;
    books = books + 10;
    books = books - 6;
    console.log(books);
37. 37.⚡ What does this code show?
    let name = "Riya";
    alert("Welcome, " + name + "!"); (a) Riya (b) Welcome, name! (c) name (d) Welcome, Riya!
38. 38.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 7;
    console.log(x + y); (a) 87 (b) Error (c) 15
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 2;
    console.log(x + y); (a) Error (b) 4 (c) 22
40. 40.⚡ What number does this code print?
    let a = 52;
    let b = 31;
    console.log(a + b);

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