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App Dev Worksheet: Functions

App development lesson 20: Functions · Set 75 · 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.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(25, 5));
  2. 2.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Riya"));     (a) greet (b) Hello, Riya! (c) Riya (d) Hello, name!
  3. 3.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(10, 2));
  4. 4.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(100, 2));
  5. 5.🧰 How do you run (call) a function called greet? (a) run greet (b) #greet (c) greet[] (d) greet()
  6. 6.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Riya"));     (a) Riya (b) Hi, name! (c) greet (d) Hi, Riya!
  7. 7.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Arjun"));     (a) Welcome, Arjun! (b) Welcome, name! (c) Arjun (d) greet
  8. 8.🧰 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
  9. 9.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(60, 6));
  10. 10.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(22));
  11. 11.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Arjun"));     (a) greet (b) Well done, name! (c) Arjun (d) Well done, Arjun!
  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 40;
    }
    show(fee(9) + fee(2));
  13. 13.🧰 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(12) + fee(9));
  14. 14.🧰 What is a function? (a) a screen size (b) a named block of code (c) a list of colours (d) a type of phone
  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 30;
    }
    show(fee(2) + fee(2));
  16. 16.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(33));
  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 40;
    }
    show(fee(9) + fee(8));
  18. 18.🧰 What does return do in a function? (a) closes the screen (b) deletes the app (c) sends back a value (d) repeats the code
  19. 19.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(19));
  20. 20.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(30));
  21. 21.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(11));
  22. 22.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(30));
  23. 23.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Arjun"));     (a) greet (b) Arjun (c) Hi, Arjun! (d) Hi, name!
  24. 24.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(35, 2));
  25. 25.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Meera"));     (a) greet (b) Welcome, name! (c) Meera (d) Welcome, Meera!
  26. 26.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Zoya"));     (a) Welcome, name! (b) Zoya (c) greet (d) Welcome, Zoya!
  27. 27.🧰 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(10) + fee(2));
  28. 28.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(90, 2));
  29. 29.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(45, 2));
  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 60;
    }
    show(fee(1) + fee(5));
  31. 31.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(40, 4));
  32. 32.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Meera"));     (a) Meera (b) greet (c) Well done, Meera! (d) Well done, name!
  33. 33.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(10, 5));
  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 20;
    }
    show(fee(3) + fee(10));
  35. 35.🧰 Why write a function? (a) to make code longer (b) to reuse code (c) to hide errors (d) to slow the app
  36. 36.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(3) + points(0));
  37. 37.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(100, 6));
  38. 38.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(4) + points(4));
  39. 39.🧰 In function tip(bill), what is bill? (a) a screen (b) a parameter (c) a loop (d) an event
  40. 40.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Zoya"));     (a) Zoya (b) Hello, name! (c) greet (d) Hello, Zoya!

Answer key

  1. 125
  2. Hello, Riya!
  3. 20
  4. 200
  5. greet()
  6. Hi, Riya!
  7. Welcome, Arjun!
  8. Well done, Riya!
  9. 360
  10. 66
  11. Well done, Arjun!
  12. 40
  13. 100
  14. a named block of code
  15. 0
  16. 99
  17. 80
  18. sends back a value
  19. 57
  20. 60
  21. 22
  22. 90
  23. Hi, Arjun!
  24. 70
  25. Welcome, Meera!
  26. Welcome, Zoya!
  27. 60
  28. 180
  29. 90
  30. 60
  31. 160
  32. Well done, Meera!
  33. 50
  34. 20
  35. to reuse code
  36. 40
  37. 600
  38. 90
  39. a parameter
  40. Hello, Zoya!

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