← Functions lesson New set →

App Dev Worksheet: Functions

App development lesson 20: Functions · Set 80 · 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.🧰 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(7) + fee(8));
  2. 2.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Meera"));     (a) Hi, name! (b) greet (c) Hi, Meera! (d) Meera
  3. 3.🧰 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(11) + fee(2));
  4. 4.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(2) + points(4));
  5. 5.🧰 In function tip(bill), what is bill? (a) an event (b) a loop (c) a parameter (d) a screen
  6. 6.🧰 How do you run (call) a function called greet? (a) greet[] (b) greet() (c) #greet (d) run greet
  7. 7.🧰 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(11) + fee(2));
  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(12));
  9. 9.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(2) + points(2));
  10. 10.🧰 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(4) + fee(4));
  11. 11.🧰 What does return do in a function? (a) repeats the code (b) closes the screen (c) sends back a value (d) deletes the app
  12. 12.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Arjun"));     (a) Arjun (b) Welcome, Arjun! (c) greet (d) Welcome, name!
  13. 13.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(37));
  14. 14.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(14));
  15. 15.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(21));
  16. 16.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(31));
  17. 17.🧰 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(2) + fee(4));
  18. 18.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(90, 2));
  19. 19.🧰 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(8) + fee(1));
  20. 20.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Arjun"));     (a) greet (b) Hi, name! (c) Hi, Arjun! (d) Arjun
  21. 21.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(5) + points(1));
  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(8) + fee(7));
  23. 23.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Meera"));     (a) Meera (b) Welcome, name! (c) Welcome, Meera! (d) greet
  24. 24.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Zoya"));     (a) Hi, Zoya! (b) Zoya (c) greet (d) Hi, name!
  25. 25.🧰 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(4));
  26. 26.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(20, 2));
  27. 27.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(12));
  28. 28.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Riya"));     (a) Well done, name! (b) greet (c) Riya (d) Well done, Riya!
  29. 29.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(8));
  30. 30.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(65, 3));
  31. 31.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(3) + points(4));
  32. 32.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(5) + points(4));
  33. 33.🧰 Why write a function? (a) to hide errors (b) to make code longer (c) to slow the app (d) to reuse code
  34. 34.🧰 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(9) + fee(4));
  35. 35.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Arjun"));     (a) Hello, name! (b) Arjun (c) greet (d) Hello, Arjun!
  36. 36.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(10, 3));
  37. 37.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(40, 3));
  38. 38.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(3));
  39. 39.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(7));
  40. 40.🧰 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(2) + fee(8));

Answer key

  1. 60
  2. Hi, Meera!
  3. 50
  4. 70
  5. a parameter
  6. greet()
  7. 20
  8. 60
  9. 50
  10. 0
  11. sends back a value
  12. Welcome, Arjun!
  13. 74
  14. 42
  15. 42
  16. 62
  17. 0
  18. 180
  19. 20
  20. Hi, Arjun!
  21. 70
  22. 80
  23. Welcome, Meera!
  24. Hi, Zoya!
  25. 0
  26. 40
  27. 24
  28. Well done, Riya!
  29. 16
  30. 195
  31. 80
  32. 100
  33. to reuse code
  34. 50
  35. Hello, Arjun!
  36. 30
  37. 120
  38. 6
  39. 21
  40. 50

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