JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 453 · 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 coins = 23;
   coins = coins + 11;
   coins = coins - 11;
   console.log(coins);
2. 2.⚡ Where does console.log() show its output? (a) on the title bar (b) in the address bar (c) on the printer (d) in the console
3. 3.⚡ Which JavaScript word writes in the console? (a) if (b) let (c) alert() (d) console.log()
4. 4.⚡ Which JavaScript word makes a new variable? (a) let (b) for (c) alert() (d) console.log()
5. 5.⚡ What does this code print? (Look at the quotes!)
   let x = "7";
   let y = 9;
   console.log(x + y); (a) 16 (b) 79 (c) Error
6. 6.⚡ What number does this code print?
   let books = 26;
   books = books + 9;
   books = books - 15;
   console.log(books);
7. 7.⚡ What does this code print? (Look at the quotes!)
   let x = "3";
   let y = 8;
   console.log(x + y); (a) 38 (b) 11 (c) Error
8. 8.⚡ What number does this code print?
   let a = 7;
   let b = 3;
   console.log(a * b);
9. 9.⚡ What does this code show?
   let name = "Aman";
   alert("Hi, " + name + "!"); (a) Hi, Aman! (b) Hi, name! (c) name (d) Aman
10. 10.⚡ Which JavaScript word shows a pop-up box? (a) let (b) alert() (c) console.log() (d) for
11. 11.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) Welcome, Riya! (b) Welcome, name! (c) Riya (d) name
12. 12.⚡ Which JavaScript word runs code when true? (a) if (b) for (c) alert() (d) console.log()
13. 13.⚡ Which JavaScript word repeats code? (a) for (b) let (c) alert() (d) if
14. 14.⚡ Which tag holds JavaScript in a page? (a) <script> (b) <style> (c) <code> (d) <js>
15. 15.⚡ What does this code show?
    let name = "Riya";
    console.log("Hi, " + name + "!"); (a) Riya (b) Hi, name! (c) Hi, Riya! (d) name
16. 16.⚡ What number does this code print?
    let coins = 11;
    coins = coins + 3;
    coins = coins - 8;
    console.log(coins);
17. 17.⚡ A JavaScript file usually ends with which extension? (a) .css (b) .js (c) .html (d) .jpg
18. 18.⚡ What number does this code print?
    let a = 4;
    let b = 7;
    console.log(a * b);
19. 19.⚡ What number does this code print?
    let books = 17;
    books = books + 3;
    books = books - 4;
    console.log(books);
20. 20.⚡ What number does this code print?
    let a = 6;
    let b = 9;
    console.log(a * b);
21. 21.⚡ What number does this code print?
    let a = 27;
    let b = 40;
    console.log(a + b);
22. 22.⚡ What number does this code print?
    let a = 32;
    let b = 30;
    console.log(a - b);
23. 23.⚡ What number does this code print?
    let a = 16;
    let b = 27;
    console.log(a + b);
24. 24.⚡ What does this code show?
    let name = "Zoya";
    alert("Well done, " + name + "!"); (a) Zoya (b) Well done, Zoya! (c) Well done, name! (d) name
25. 25.⚡ What number does this code print?
    let runs = 28;
    runs = runs + 12;
    runs = runs - 1;
    console.log(runs);
26. 26.⚡ What number does this code print?
    let a = 17;
    let b = 13;
    console.log(a - b);
27. 27.⚡ Which word makes a new variable? (a) give (b) let (c) put (d) make
28. 28.⚡ What number does this code print?
    let a = 49;
    let b = 17;
    console.log(a - b);
29. 29.⚡ What number does this code print?
    let a = 4;
    let b = 4;
    console.log(a * b);
30. 30.⚡ What does this code show?
    let name = "Aman";
    alert("Welcome, " + name + "!"); (a) name (b) Welcome, Aman! (c) Welcome, name! (d) Aman
31. 31.⚡ What number does this code print?
    let a = 4;
    let b = 11;
    console.log(a * b);
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 8;
    console.log(x + y); (a) Error (b) 14 (c) 68
33. 33.⚡ What number does this code print?
    let a = 31;
    let b = 5;
    console.log(a + b);
34. 34.⚡ What does this code show?
    let name = "Aman";
    console.log("Hi, " + name + "!"); (a) name (b) Hi, name! (c) Aman (d) Hi, Aman!
35. 35.⚡ What number does this code print?
    let apples = 21;
    apples = apples + 13;
    apples = apples - 33;
    console.log(apples);
36. 36.⚡ What number does this code print?
    let books = 10;
    books = books + 15;
    books = books - 19;
    console.log(books);
37. 37.⚡ What number does this code print?
    let runs = 27;
    runs = runs + 18;
    runs = runs - 4;
    console.log(runs);
38. 38.⚡ What number does this code print?
    let a = 20;
    let b = 14;
    console.log(a - b);
39. 39.⚡ What number does this code print?
    let a = 26;
    let b = 11;
    console.log(a - b);
40. 40.⚡ What number does this code print?
    let a = 12;
    let b = 10;
    console.log(a * b);

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