JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 330 · 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 a = 12;
   let b = 11;
   console.log(a * b);
2. 2.⚡ Which JavaScript word shows a pop-up box? (a) console.log() (b) alert() (c) for (d) let
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 show?
   let name = "Meera";
   alert("Hi, " + name + "!"); (a) Hi, name! (b) name (c) Meera (d) Hi, Meera!
5. 5.⚡ Which JavaScript word runs code when true? (a) let (b) for (c) alert() (d) if
6. 6.⚡ What does JavaScript add to a web page? (a) the domain name (b) actions and changes (c) the page title (d) only colours
7. 7.⚡ What number does this code print?
   let a = 2;
   let b = 9;
   console.log(a * b);
8. 8.⚡ Which JavaScript word makes a new variable? (a) for (b) if (c) alert() (d) let
9. 9.⚡ Which word makes a new variable? (a) make (b) let (c) give (d) put
10. 10.⚡ What number does this code print?
    let marks = 9;
    marks = marks + 16;
    marks = marks - 2;
    console.log(marks);
11. 11.⚡ What number does this code print?
    let a = 14;
    let b = 6;
    console.log(a + b);
12. 12.⚡ What number does this code print?
    let a = 11;
    let b = 13;
    console.log(a + b);
13. 13.⚡ Where does console.log() show its output? (a) on the printer (b) in the address bar (c) on the title bar (d) in the console
14. 14.⚡ Which JavaScript word repeats code? (a) console.log() (b) for (c) alert() (d) let
15. 15.⚡ Which JavaScript word writes in the console? (a) for (b) console.log() (c) if (d) alert()
16. 16.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 6;
    console.log(x + y); (a) Error (b) 13 (c) 76
17. 17.⚡ What number does this code print?
    let score = 13;
    score = score + 5;
    score = score - 16;
    console.log(score);
18. 18.⚡ What number does this code print?
    let a = 14;
    let b = 30;
    console.log(a + b);
19. 19.⚡ What does this code show?
    let name = "Kabir";
    alert("Hi, " + name + "!"); (a) name (b) Hi, Kabir! (c) Kabir (d) Hi, name!
20. 20.⚡ What does this code show?
    let name = "Arjun";
    alert("Hello, " + name + "!"); (a) Arjun (b) Hello, name! (c) Hello, Arjun! (d) name
21. 21.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 1;
    console.log(x + y); (a) Error (b) 61 (c) 7
22. 22.⚡ What number does this code print?
    let runs = 10;
    runs = runs + 13;
    runs = runs - 15;
    console.log(runs);
23. 23.⚡ What does this code show?
    let name = "Riya";
    alert("Well done, " + name + "!"); (a) name (b) Well done, Riya! (c) Well done, name! (d) Riya
24. 24.⚡ What does this code show?
    let name = "Aman";
    console.log("Welcome, " + name + "!"); (a) name (b) Aman (c) Welcome, name! (d) Welcome, Aman!
25. 25.⚡ What does this code show?
    let name = "Zoya";
    alert("Hi, " + name + "!"); (a) Hi, Zoya! (b) Hi, name! (c) Zoya (d) name
26. 26.⚡ What number does this code print?
    let a = 49;
    let b = 33;
    console.log(a - b);
27. 27.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 3;
    console.log(x + y); (a) 12 (b) 93 (c) Error
28. 28.⚡ What number does this code print?
    let a = 11;
    let b = 5;
    console.log(a * b);
29. 29.⚡ What does this code print? (Look at the quotes!)
    let x = "6";
    let y = 2;
    console.log(x + y); (a) 8 (b) 62 (c) Error
30. 30.⚡ What number does this code print?
    let a = 30;
    let b = 13;
    console.log(a - b);
31. 31.⚡ What number does this code print?
    let runs = 10;
    runs = runs + 3;
    runs = runs - 8;
    console.log(runs);
32. 32.⚡ What does this code show?
    let name = "Kabir";
    console.log("Hello, " + name + "!"); (a) Kabir (b) name (c) Hello, Kabir! (d) Hello, name!
33. 33.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hello, " + name + "!"); (a) Hello, name! (b) Arjun (c) name (d) Hello, Arjun!
34. 34.⚡ What number does this code print?
    let runs = 24;
    runs = runs + 11;
    runs = runs - 33;
    console.log(runs);
35. 35.⚡ What does this code print? (Look at the quotes!)
    let x = "1";
    let y = 3;
    console.log(x + y); (a) Error (b) 4 (c) 13
36. 36.⚡ What does this code show?
    let name = "Zoya";
    alert("Hello, " + name + "!"); (a) Zoya (b) Hello, name! (c) name (d) Hello, Zoya!
37. 37.⚡ What number does this code print?
    let a = 10;
    let b = 5;
    console.log(a - b);
38. 38.⚡ What number does this code print?
    let a = 43;
    let b = 31;
    console.log(a + b);
39. 39.⚡ A JavaScript file usually ends with which extension? (a) .jpg (b) .css (c) .html (d) .js
40. 40.⚡ What number does this code print?
    let a = 12;
    let b = 9;
    console.log(a * b);

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