JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 612 · 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 print? (Look at the quotes!)
   let x = "3";
   let y = 3;
   console.log(x + y); (a) Error (b) 6 (c) 33
2. 2.⚡ What number does this code print?
   let a = 36;
   let b = 7;
   console.log(a - b);
3. 3.⚡ What number does this code print?
   let a = 12;
   let b = 14;
   console.log(a + b);
4. 4.⚡ What number does this code print?
   let a = 2;
   let b = 4;
   console.log(a * b);
5. 5.⚡ What number does this code print?
   let a = 8;
   let b = 5;
   console.log(a * b);
6. 6.⚡ Where does console.log() show its output? (a) in the address bar (b) on the title bar (c) on the printer (d) in the console
7. 7.⚡ Which JavaScript word writes in the console? (a) let (b) console.log() (c) for (d) alert()
8. 8.⚡ Which JavaScript word shows a pop-up box? (a) let (b) alert() (c) console.log() (d) if
9. 9.⚡ What does this code print? (Look at the quotes!)
   let x = "9";
   let y = 1;
   console.log(x + y); (a) 91 (b) 10 (c) Error
10. 10.⚡ Which JavaScript word runs code when true? (a) if (b) for (c) console.log() (d) let
11. 11.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .js (c) .html (d) .css
12. 12.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 2;
    console.log(x + y); (a) 82 (b) 10 (c) Error
13. 13.⚡ What number does this code print?
    let a = 8;
    let b = 2;
    console.log(a * b);
14. 14.⚡ What number does this code print?
    let a = 8;
    let b = 19;
    console.log(a + b);
15. 15.⚡ Which word makes a new variable? (a) give (b) make (c) put (d) let
16. 16.⚡ What number does this code print?
    let a = 46;
    let b = 28;
    console.log(a + b);
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 3;
    console.log(x + y); (a) 43 (b) 7 (c) Error
18. 18.⚡ What does this code show?
    let name = "Riya";
    alert("Welcome, " + name + "!"); (a) Riya (b) Welcome, Riya! (c) name (d) Welcome, name!
19. 19.⚡ What does alert() show? (a) a picture (b) a table (c) a pop-up box (d) a new tab
20. 20.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <js> (c) <style> (d) <code>
21. 21.⚡ What number does this code print?
    let score = 10;
    score = score + 6;
    score = score - 13;
    console.log(score);
22. 22.⚡ What number does this code print?
    let apples = 7;
    apples = apples + 18;
    apples = apples - 23;
    console.log(apples);
23. 23.⚡ Which JavaScript word repeats code? (a) for (b) console.log() (c) alert() (d) if
24. 24.⚡ What number does this code print?
    let a = 8;
    let b = 23;
    console.log(a + b);
25. 25.⚡ What number does this code print?
    let a = 48;
    let b = 17;
    console.log(a + b);
26. 26.⚡ What number does this code print?
    let coins = 25;
    coins = coins + 16;
    coins = coins - 12;
    console.log(coins);
27. 27.⚡ What number does this code print?
    let score = 10;
    score = score + 17;
    score = score - 27;
    console.log(score);
28. 28.⚡ What number does this code print?
    let score = 9;
    score = score + 18;
    score = score - 23;
    console.log(score);
29. 29.⚡ What does this code show?
    let name = "Arjun";
    console.log("Welcome, " + name + "!"); (a) Arjun (b) Welcome, name! (c) Welcome, Arjun! (d) name
30. 30.⚡ What number does this code print?
    let a = 9;
    let b = 3;
    console.log(a * b);
31. 31.⚡ What number does this code print?
    let a = 41;
    let b = 35;
    console.log(a + b);
32. 32.⚡ What number does this code print?
    let a = 23;
    let b = 7;
    console.log(a - b);
33. 33.⚡ What number does this code print?
    let a = 9;
    let b = 4;
    console.log(a * b);
34. 34.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!"); (a) Hello, name! (b) Arjun (c) name (d) Hello, Arjun!
35. 35.⚡ What number does this code print?
    let runs = 20;
    runs = runs + 3;
    runs = runs - 22;
    console.log(runs);
36. 36.⚡ Which JavaScript word makes a new variable? (a) console.log() (b) if (c) for (d) let
37. 37.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 4;
    console.log(x + y); (a) 6 (b) Error (c) 24
38. 38.⚡ What does this code show?
    let name = "Meera";
    alert("Hello, " + name + "!"); (a) Hello, name! (b) Hello, Meera! (c) Meera (d) name
39. 39.⚡ What number does this code print?
    let books = 12;
    books = books + 16;
    books = books - 21;
    console.log(books);
40. 40.⚡ What number does this code print?
    let a = 38;
    let b = 32;
    console.log(a - b);

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