JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 180 · 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 apples = 24;
   apples = apples + 14;
   apples = apples - 23;
   console.log(apples);
2. 2.⚡ What does this code show?
   let name = "Meera";
   alert("Welcome, " + name + "!"); (a) Meera (b) Welcome, Meera! (c) name (d) Welcome, name!
3. 3.⚡ What does JavaScript add to a web page? (a) only colours (b) the domain name (c) the page title (d) actions and changes
4. 4.⚡ What does this code show?
   let name = "Zoya";
   alert("Hello, " + name + "!"); (a) name (b) Hello, name! (c) Hello, Zoya! (d) Zoya
5. 5.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <js> (c) <script> (d) <code>
6. 6.⚡ Which JavaScript word repeats code? (a) alert() (b) for (c) if (d) console.log()
7. 7.⚡ What number does this code print?
   let a = 35;
   let b = 34;
   console.log(a - b);
8. 8.⚡ Which JavaScript word shows a pop-up box? (a) if (b) for (c) alert() (d) let
9. 9.⚡ What number does this code print?
   let a = 11;
   let b = 14;
   console.log(a + b);
10. 10.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .jpg (c) .html (d) .css
11. 11.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 1;
    console.log(x + y); (a) Error (b) 8 (c) 71
12. 12.⚡ What does this code show?
    let name = "Arjun";
    console.log("Welcome, " + name + "!"); (a) name (b) Arjun (c) Welcome, name! (d) Welcome, Arjun!
13. 13.⚡ What does this code show?
    let name = "Aman";
    console.log("Hello, " + name + "!"); (a) Aman (b) name (c) Hello, Aman! (d) Hello, name!
14. 14.⚡ What does alert() show? (a) a pop-up box (b) a table (c) a new tab (d) a picture
15. 15.⚡ Which JavaScript word runs code when true? (a) if (b) alert() (c) let (d) console.log()
16. 16.⚡ What number does this code print?
    let score = 5;
    score = score + 12;
    score = score - 17;
    console.log(score);
17. 17.⚡ What number does this code print?
    let a = 22;
    let b = 12;
    console.log(a - b);
18. 18.⚡ What number does this code print?
    let a = 12;
    let b = 10;
    console.log(a * b);
19. 19.⚡ What does this code show?
    let name = "Riya";
    console.log("Hi, " + name + "!"); (a) Hi, Riya! (b) Hi, name! (c) Riya (d) name
20. 20.⚡ Where does console.log() show its output? (a) on the printer (b) on the title bar (c) in the console (d) in the address bar
21. 21.⚡ What number does this code print?
    let a = 18;
    let b = 4;
    console.log(a - b);
22. 22.⚡ Which JavaScript word writes in the console? (a) console.log() (b) for (c) if (d) alert()
23. 23.⚡ What number does this code print?
    let a = 34;
    let b = 2;
    console.log(a - b);
24. 24.⚡ What does this code show?
    let name = "Zoya";
    alert("Welcome, " + name + "!"); (a) Welcome, name! (b) Welcome, Zoya! (c) Zoya (d) name
25. 25.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) Hello, Meera! (b) Meera (c) Hello, name! (d) name
26. 26.⚡ What number does this code print?
    let a = 14;
    let b = 20;
    console.log(a + b);
27. 27.⚡ Which JavaScript word makes a new variable? (a) if (b) alert() (c) let (d) for
28. 28.⚡ Which word makes a new variable? (a) let (b) make (c) put (d) give
29. 29.⚡ What number does this code print?
    let score = 10;
    score = score + 17;
    score = score - 26;
    console.log(score);
30. 30.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 6;
    console.log(x + y); (a) 13 (b) 76 (c) Error
31. 31.⚡ What number does this code print?
    let a = 39;
    let b = 3;
    console.log(a + b);
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 1;
    console.log(x + y); (a) 51 (b) Error (c) 6
33. 33.⚡ What number does this code print?
    let a = 29;
    let b = 14;
    console.log(a - b);
34. 34.⚡ What does this code show?
    let name = "Riya";
    alert("Well done, " + name + "!"); (a) Riya (b) Well done, Riya! (c) Well done, name! (d) name
35. 35.⚡ What does this code show?
    let name = "Zoya";
    alert("Well done, " + name + "!"); (a) name (b) Zoya (c) Well done, name! (d) Well done, Zoya!
36. 36.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 5;
    console.log(x + y); (a) 9 (b) Error (c) 45
37. 37.⚡ What does this code print? (Look at the quotes!)
    let x = "5";
    let y = 9;
    console.log(x + y); (a) 14 (b) 59 (c) Error
38. 38.⚡ What number does this code print?
    let a = 49;
    let b = 10;
    console.log(a - b);
39. 39.⚡ What number does this code print?
    let a = 55;
    let b = 25;
    console.log(a - b);
40. 40.⚡ What does this code show?
    let name = "Riya";
    console.log("Welcome, " + name + "!"); (a) name (b) Welcome, Riya! (c) Riya (d) Welcome, name!

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