JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 855 · 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 word makes a new variable? (a) make (b) let (c) put (d) give
2. 2.⚡ What number does this code print?
   let a = 49;
   let b = 31;
   console.log(a + b);
3. 3.⚡ What does this code print? (Look at the quotes!)
   let x = "3";
   let y = 2;
   console.log(x + y); (a) 5 (b) 32 (c) Error
4. 4.⚡ 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
5. 5.⚡ Which JavaScript word makes a new variable? (a) let (b) if (c) alert() (d) for
6. 6.⚡ What number does this code print?
   let a = 5;
   let b = 26;
   console.log(a + b);
7. 7.⚡ Which JavaScript word writes in the console? (a) let (b) for (c) alert() (d) console.log()
8. 8.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) alert() (c) if (d) let
9. 9.⚡ What number does this code print?
   let a = 30;
   let b = 4;
   console.log(a - b);
10. 10.⚡ What number does this code print?
    let a = 10;
    let b = 2;
    console.log(a * b);
11. 11.⚡ What number does this code print?
    let a = 11;
    let b = 10;
    console.log(a * b);
12. 12.⚡ Which JavaScript word runs code when true? (a) let (b) if (c) alert() (d) console.log()
13. 13.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 5;
    console.log(x + y); (a) 11 (b) 65 (c) Error
14. 14.⚡ What number does this code print?
    let a = 56;
    let b = 28;
    console.log(a - b);
15. 15.⚡ What number does this code print?
    let a = 20;
    let b = 13;
    console.log(a - b);
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "8";
    let y = 1;
    console.log(x + y); (a) 81 (b) 9 (c) Error
17. 17.⚡ What number does this code print?
    let a = 14;
    let b = 18;
    console.log(a + b);
18. 18.⚡ What number does this code print?
    let a = 2;
    let b = 9;
    console.log(a * b);
19. 19.⚡ What does this code show?
    let name = "Zoya";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) Zoya (c) Hello, Zoya! (d) name
20. 20.⚡ What number does this code print?
    let score = 25;
    score = score + 4;
    score = score - 24;
    console.log(score);
21. 21.⚡ What number does this code print?
    let a = 43;
    let b = 33;
    console.log(a - b);
22. 22.⚡ Which JavaScript word repeats code? (a) alert() (b) for (c) let (d) console.log()
23. 23.⚡ A JavaScript file usually ends with which extension? (a) .html (b) .css (c) .jpg (d) .js
24. 24.⚡ What does JavaScript add to a web page? (a) only colours (b) the domain name (c) actions and changes (d) the page title
25. 25.⚡ What number does this code print?
    let a = 31;
    let b = 14;
    console.log(a - b);
26. 26.⚡ What number does this code print?
    let a = 12;
    let b = 11;
    console.log(a * b);
27. 27.⚡ What does this code show?
    let name = "Riya";
    alert("Hi, " + name + "!"); (a) name (b) Hi, Riya! (c) Riya (d) Hi, name!
28. 28.⚡ What number does this code print?
    let a = 11;
    let b = 12;
    console.log(a * b);
29. 29.⚡ What number does this code print?
    let marks = 5;
    marks = marks + 3;
    marks = marks - 7;
    console.log(marks);
30. 30.⚡ Where does console.log() show its output? (a) on the title bar (b) in the address bar (c) in the console (d) on the printer
31. 31.⚡ What number does this code print?
    let a = 8;
    let b = 7;
    console.log(a * b);
32. 32.⚡ What does this code show?
    let name = "Aman";
    console.log("Hi, " + name + "!"); (a) name (b) Hi, Aman! (c) Aman (d) Hi, name!
33. 33.⚡ What number does this code print?
    let a = 42;
    let b = 37;
    console.log(a + b);
34. 34.⚡ What number does this code print?
    let a = 55;
    let b = 1;
    console.log(a + b);
35. 35.⚡ 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
36. 36.⚡ What number does this code print?
    let a = 8;
    let b = 11;
    console.log(a * b);
37. 37.⚡ What number does this code print?
    let coins = 30;
    coins = coins + 12;
    coins = coins - 6;
    console.log(coins);
38. 38.⚡ Which tag holds JavaScript in a page? (a) <code> (b) <js> (c) <style> (d) <script>
39. 39.⚡ What number does this code print?
    let a = 30;
    let b = 24;
    console.log(a - b);
40. 40.⚡ What number does this code print?
    let score = 6;
    score = score + 13;
    score = score - 13;
    console.log(score);

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