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App Dev Worksheet: Functions

App development lesson 20: Functions · Set 616 · 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 60;
    }
    show(fee(1) + fee(2));
  2. 2.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(10));
  3. 3.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Aman"));     (a) Hello, name! (b) Hello, Aman! (c) Aman (d) greet
  4. 4.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Arjun"));     (a) Welcome, Arjun! (b) greet (c) Arjun (d) Welcome, name!
  5. 5.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(11));
  6. 6.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Aman"));     (a) Aman (b) greet (c) Well done, name! (d) Well done, Aman!
  7. 7.🧰 In function tip(bill), what is bill? (a) an event (b) a loop (c) a parameter (d) a screen
  8. 8.🧰 What is a function? (a) a named block of code (b) a type of phone (c) a list of colours (d) a screen size
  9. 9.🧰 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(5));
  10. 10.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Zoya"));     (a) Welcome, name! (b) Zoya (c) Welcome, Zoya! (d) greet
  11. 11.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(4) + points(0));
  12. 12.🧰 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(1) + fee(5));
  13. 13.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(12));
  14. 14.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(20, 4));
  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 50;
    }
    show(fee(3) + fee(1));
  16. 16.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Riya"));     (a) Well done, name! (b) Well done, Riya! (c) greet (d) Riya
  17. 17.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(100, 6));
  18. 18.🧰 Why write a function? (a) to reuse code (b) to hide errors (c) to make code longer (d) to slow the app
  19. 19.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(5) + points(5));
  20. 20.🧰 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(3) + fee(8));
  21. 21.🧰 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(1) + fee(2));
  22. 22.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(25, 5));
  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 20;
    }
    show(fee(3) + fee(10));
  24. 24.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Arjun"));     (a) Arjun (b) greet (c) Well done, name! (d) Well done, Arjun!
  25. 25.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(25, 2));
  26. 26.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(10, 4));
  27. 27.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(25, 6));
  28. 28.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Riya"));     (a) greet (b) Hi, name! (c) Riya (d) Hi, Riya!
  29. 29.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Meera"));     (a) Welcome, Meera! (b) Meera (c) Welcome, name! (d) greet
  30. 30.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(5) + points(2));
  31. 31.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(50, 4));
  32. 32.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(15));
  33. 33.🧰 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(5) + fee(4));
  34. 34.🧰 What does return do in a function? (a) deletes the app (b) repeats the code (c) sends back a value (d) closes the screen
  35. 35.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(4) + points(5));
  36. 36.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(6));
  37. 37.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(5));
  38. 38.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(5) + points(0));
  39. 39.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(21));
  40. 40.🧰 How do you run (call) a function called greet? (a) #greet (b) greet() (c) run greet (d) greet[]

Answer key

  1. 0
  2. 30
  3. Hello, Aman!
  4. Welcome, Arjun!
  5. 33
  6. Well done, Aman!
  7. a parameter
  8. a named block of code
  9. 20
  10. Welcome, Zoya!
  11. 50
  12. 20
  13. 36
  14. 80
  15. 0
  16. Well done, Riya!
  17. 600
  18. to reuse code
  19. 110
  20. 20
  21. 0
  22. 125
  23. 20
  24. Well done, Arjun!
  25. 50
  26. 40
  27. 150
  28. Hi, Riya!
  29. Welcome, Meera!
  30. 80
  31. 200
  32. 30
  33. 20
  34. sends back a value
  35. 100
  36. 18
  37. 10
  38. 60
  39. 42
  40. greet()

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