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App Dev Worksheet: Functions

App development lesson 20: Functions · Set 966 · 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 does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Kabir"));     (a) greet (b) Well done, name! (c) Kabir (d) Well done, Kabir!
  2. 2.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(11));
  3. 3.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(1) + points(3));
  4. 4.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(11));
  5. 5.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Zoya"));     (a) Hello, Zoya! (b) Zoya (c) Hello, name! (d) greet
  6. 6.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(15, 2));
  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 30;
    }
    show(fee(10) + fee(10));
  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(1) + fee(8));
  9. 9.🧰 What is a function? (a) a type of phone (b) a list of colours (c) a named block of code (d) a screen size
  10. 10.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Meera"));     (a) greet (b) Welcome, Meera! (c) Welcome, name! (d) Meera
  11. 11.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(17));
  12. 12.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(100, 6));
  13. 13.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Arjun"));     (a) greet (b) Arjun (c) Welcome, Arjun! (d) Welcome, name!
  14. 14.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(4) + points(0));
  15. 15.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(90, 3));
  16. 16.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Arjun"));     (a) Hi, name! (b) Hi, Arjun! (c) Arjun (d) greet
  17. 17.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Meera"));     (a) greet (b) Hello, name! (c) Hello, Meera! (d) Meera
  18. 18.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Kabir"));     (a) Hi, name! (b) Hi, Kabir! (c) Kabir (d) greet
  19. 19.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(3) + points(2));
  20. 20.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(5) + points(4));
  21. 21.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(35));
  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 30;
    }
    show(fee(9) + fee(5));
  23. 23.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(35, 2));
  24. 24.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(3) + points(4));
  25. 25.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(55, 6));
  26. 26.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(2) + points(0));
  27. 27.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(1) + points(4));
  28. 28.🧰 What does return do in a function? (a) sends back a value (b) closes the screen (c) deletes the app (d) repeats the code
  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 20;
    }
    show(fee(3) + fee(11));
  30. 30.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(50, 5));
  31. 31.🧰 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(6) + fee(9));
  32. 32.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(30, 3));
  33. 33.🧰 In function tip(bill), what is bill? (a) a parameter (b) an event (c) a screen (d) a loop
  34. 34.🧰 Why write a function? (a) to make code longer (b) to slow the app (c) to reuse code (d) to hide errors
  35. 35.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(8));
  36. 36.🧰 What does this code show?
    function greet(name) {
      return "Hi, " + name + "!";
    }
    show(greet("Aman"));     (a) Hi, Aman! (b) Aman (c) greet (d) Hi, name!
  37. 37.🧰 How do you run (call) a function called greet? (a) #greet (b) greet() (c) greet[] (d) run greet
  38. 38.🧰 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(3) + fee(8));
  39. 39.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(50, 2));
  40. 40.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Aman"));     (a) greet (b) Welcome, Aman! (c) Aman (d) Welcome, name!

Answer key

  1. Well done, Kabir!
  2. 22
  3. 50
  4. 33
  5. Hello, Zoya!
  6. 30
  7. 60
  8. 30
  9. a named block of code
  10. Welcome, Meera!
  11. 51
  12. 600
  13. Welcome, Arjun!
  14. 50
  15. 270
  16. Hi, Arjun!
  17. Hello, Meera!
  18. Hi, Kabir!
  19. 60
  20. 100
  21. 105
  22. 60
  23. 70
  24. 80
  25. 330
  26. 30
  27. 60
  28. sends back a value
  29. 20
  30. 250
  31. 40
  32. 90
  33. a parameter
  34. to reuse code
  35. 16
  36. Hi, Aman!
  37. greet()
  38. 30
  39. 100
  40. Welcome, Aman!

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