← Functions lesson New set →

App Dev Worksheet: Functions

App development lesson 20: Functions · Set 634 · 40 questions
TalentJR

Developer's tip (Write once, use often): function name(parameter) { …; return result; } — call it with name(value). Work out each call separately, then finish the line. Inside a function, if / return can give different results for different inputs.

NameDateTime takenScore ___ / 40
  1. 1.🧰 How do you run (call) a function called greet? (a) greet[] (b) run greet (c) #greet (d) greet()
  2. 2.🧰 What is a function? (a) a named block of code (b) a type of phone (c) a list of colours (d) a screen size
  3. 3.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(60, 5));
  4. 4.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(80, 4));
  5. 5.🧰 What does return do in a function? (a) deletes the app (b) repeats the code (c) closes the screen (d) sends back a value
  6. 6.🧰 In function tip(bill), what is bill? (a) a screen (b) an event (c) a loop (d) a parameter
  7. 7.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(3) + points(4));
  8. 8.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 30;
    }
    show(fee(5) + fee(6));
  9. 9.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Aman"));     (a) greet (b) Hello, Aman! (c) Aman (d) Hello, name!
  10. 10.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(18));
  11. 11.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(60, 6));
  12. 12.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Riya"));     (a) greet (b) Well done, Riya! (c) Riya (d) Well done, name!
  13. 13.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(30, 2));
  14. 14.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(70, 2));
  15. 15.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 20;
    }
    show(fee(4) + fee(6));
  16. 16.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(39));
  17. 17.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(21));
  18. 18.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(3));
  19. 19.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Aman"));     (a) greet (b) Hi, Aman! (c) Aman (d) Hi, name!
  20. 20.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Arjun"));     (a) Welcome, name! (b) Arjun (c) Welcome, Arjun! (d) greet
  21. 21.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(31));
  22. 22.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 40;
    }
    show(fee(10) + fee(9));
  23. 23.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 50;
    }
    show(fee(5) + fee(1));
  24. 24.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(4) + points(2));
  25. 25.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(3) + points(3));
  26. 26.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(35, 4));
  27. 27.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Meera"));     (a) Welcome, Meera! (b) Welcome, name! (c) Meera (d) greet
  28. 28.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(5) + points(0));
  29. 29.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 30;
    }
    show(fee(10) + fee(4));
  30. 30.🧰 A museum app works out the entry fee. What number does this code show?
    function fee(age) {
      if (age < 5) {
        return 0;
      }
      return 50;
    }
    show(fee(3) + fee(12));
  31. 31.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(10, 5));
  32. 32.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Riya"));     (a) Hi, Riya! (b) Riya (c) Hi, name! (d) greet
  33. 33.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(85, 4));
  34. 34.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Arjun"));     (a) greet (b) Arjun (c) Hi, Arjun! (d) Hi, name!
  35. 35.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Zoya"));     (a) Zoya (b) greet (c) Hi, name! (d) Hi, Zoya!
  36. 36.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Riya"));     (a) greet (b) Riya (c) Hello, Riya! (d) Hello, name!
  37. 37.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(1) + points(1));
  38. 38.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(35));
  39. 39.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(13));
  40. 40.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Kabir"));     (a) greet (b) Hello, Kabir! (c) Kabir (d) Hello, name!

Answer key

  1. greet()
  2. a named block of code
  3. 300
  4. 320
  5. sends back a value
  6. a parameter
  7. 80
  8. 60
  9. Hello, Aman!
  10. 54
  11. 360
  12. Well done, Riya!
  13. 60
  14. 140
  15. 20
  16. 78
  17. 63
  18. 6
  19. Hi, Aman!
  20. Welcome, Arjun!
  21. 62
  22. 80
  23. 50
  24. 70
  25. 70
  26. 140
  27. Welcome, Meera!
  28. 60
  29. 30
  30. 50
  31. 50
  32. Hi, Riya!
  33. 340
  34. Hi, Arjun!
  35. Hi, Zoya!
  36. Hello, Riya!
  37. 30
  38. 70
  39. 26
  40. Hello, Kabir!

Free app development lessons, practice and worksheets at talentjr.in/app-development-for-students