JavaScript Worksheet: Basics

HTML and CSS lesson 25: JavaScript basics · Set 399 · 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 = 53;
   let b = 23;
   console.log(a + b);
2. 2.⚡ Which JavaScript word makes a new variable? (a) for (b) alert() (c) if (d) let
3. 3.⚡ What does this code show?
   let name = "Kabir";
   alert("Hello, " + name + "!"); (a) name (b) Hello, name! (c) Kabir (d) Hello, Kabir!
4. 4.⚡ What does this code print? (Look at the quotes!)
   let x = "8";
   let y = 7;
   console.log(x + y); (a) Error (b) 15 (c) 87
5. 5.⚡ What number does this code print?
   let coins = 18;
   coins = coins + 2;
   coins = coins - 9;
   console.log(coins);
6. 6.⚡ Which JavaScript word writes in the console? (a) alert() (b) let (c) for (d) console.log()
7. 7.⚡ What number does this code print?
   let a = 8;
   let b = 6;
   console.log(a * b);
8. 8.⚡ Which word makes a new variable? (a) give (b) make (c) put (d) let
9. 9.⚡ What does this code print? (Look at the quotes!)
   let x = "2";
   let y = 9;
   console.log(x + y); (a) 29 (b) Error (c) 11
10. 10.⚡ What does this code print? (Look at the quotes!)
    let x = "7";
    let y = 4;
    console.log(x + y); (a) 11 (b) Error (c) 74
11. 11.⚡ Which JavaScript word runs code when true? (a) console.log() (b) for (c) if (d) let
12. 12.⚡ A JavaScript file usually ends with which extension? (a) .js (b) .html (c) .jpg (d) .css
13. 13.⚡ What does this code show?
    let name = "Riya";
    alert("Welcome, " + name + "!"); (a) Riya (b) Welcome, Riya! (c) Welcome, name! (d) name
14. 14.⚡ What does this code print? (Look at the quotes!)
    let x = "4";
    let y = 1;
    console.log(x + y); (a) Error (b) 41 (c) 5
15. 15.⚡ What does this code show?
    let name = "Arjun";
    alert("Welcome, " + name + "!"); (a) Welcome, name! (b) name (c) Welcome, Arjun! (d) Arjun
16. 16.⚡ What number does this code print?
    let a = 37;
    let b = 23;
    console.log(a + b);
17. 17.⚡ What does this code print? (Look at the quotes!)
    let x = "9";
    let y = 4;
    console.log(x + y); (a) Error (b) 94 (c) 13
18. 18.⚡ What does this code show?
    let name = "Zoya";
    alert("Well done, " + name + "!"); (a) name (b) Well done, Zoya! (c) Well done, name! (d) Zoya
19. 19.⚡ What number does this code print?
    let coins = 6;
    coins = coins + 8;
    coins = coins - 4;
    console.log(coins);
20. 20.⚡ What does alert() show? (a) a table (b) a pop-up box (c) a new tab (d) a picture
21. 21.⚡ What does this code show?
    let name = "Arjun";
    alert("Well done, " + name + "!"); (a) Well done, name! (b) Arjun (c) Well done, Arjun! (d) name
22. 22.⚡ What does this code show?
    let name = "Riya";
    alert("Hello, " + name + "!"); (a) Hello, name! (b) name (c) Riya (d) Hello, Riya!
23. 23.⚡ What number does this code print?
    let a = 22;
    let b = 19;
    console.log(a - b);
24. 24.⚡ Which tag holds JavaScript in a page? (a) <style> (b) <js> (c) <script> (d) <code>
25. 25.⚡ What number does this code print?
    let a = 9;
    let b = 5;
    console.log(a - b);
26. 26.⚡ What number does this code print?
    let score = 25;
    score = score + 5;
    score = score - 7;
    console.log(score);
27. 27.⚡ Where does console.log() show its output? (a) on the title bar (b) in the console (c) in the address bar (d) on the printer
28. 28.⚡ What number does this code print?
    let apples = 5;
    apples = apples + 19;
    apples = apples - 6;
    console.log(apples);
29. 29.⚡ What number does this code print?
    let marks = 29;
    marks = marks + 10;
    marks = marks - 28;
    console.log(marks);
30. 30.⚡ Which JavaScript word shows a pop-up box? (a) let (b) if (c) for (d) alert()
31. 31.⚡ What does this code show?
    let name = "Meera";
    console.log("Hello, " + name + "!"); (a) name (b) Hello, Meera! (c) Hello, name! (d) Meera
32. 32.⚡ What does this code print? (Look at the quotes!)
    let x = "3";
    let y = 8;
    console.log(x + y); (a) Error (b) 11 (c) 38
33. 33.⚡ What does this code show?
    let name = "Arjun";
    console.log("Hello, " + name + "!"); (a) Arjun (b) Hello, name! (c) name (d) Hello, Arjun!
34. 34.⚡ What number does this code print?
    let a = 4;
    let b = 4;
    console.log(a * b);
35. 35.⚡ What number does this code print?
    let a = 7;
    let b = 6;
    console.log(a * b);
36. 36.⚡ What number does this code print?
    let a = 9;
    let b = 9;
    console.log(a * b);
37. 37.⚡ What number does this code print?
    let a = 16;
    let b = 38;
    console.log(a + b);
38. 38.⚡ What does this code show?
    let name = "Arjun";
    alert("Hi, " + name + "!"); (a) name (b) Hi, name! (c) Arjun (d) Hi, Arjun!
39. 39.⚡ What does this code print? (Look at the quotes!)
    let x = "2";
    let y = 1;
    console.log(x + y); (a) 21 (b) Error (c) 3
40. 40.⚡ What number does this code print?
    let a = 48;
    let b = 35;
    console.log(a + b);

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