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App Dev Worksheet: Functions

App development lesson 20: Functions · Set 382 · 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(100, 5));
  2. 2.🧰 How do you run (call) a function called greet? (a) #greet (b) greet() (c) run greet (d) greet[]
  3. 3.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(24));
  4. 4.🧰 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!
  5. 5.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Kabir"));     (a) Hello, name! (b) Hello, Kabir! (c) Kabir (d) greet
  6. 6.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(2) + points(3));
  7. 7.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Riya"));     (a) greet (b) Well done, name! (c) Riya (d) Well done, Riya!
  8. 8.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(2) + points(5));
  9. 9.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Zoya"));     (a) greet (b) Zoya (c) Welcome, name! (d) Welcome, Zoya!
  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 30;
    }
    show(fee(4) + fee(7));
  11. 11.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Kabir"));     (a) Kabir (b) Well done, name! (c) greet (d) Well done, Kabir!
  12. 12.🧰 In function tip(bill), what is bill? (a) an event (b) a screen (c) a loop (d) a parameter
  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(10) + fee(11));
  14. 14.🧰 What does return do in a function? (a) deletes the app (b) closes the screen (c) repeats the code (d) sends back a value
  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 40;
    }
    show(fee(7) + fee(6));
  16. 16.🧰 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(4) + fee(3));
  17. 17.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(40));
  18. 18.🧰 What is a function? (a) a list of colours (b) a type of phone (c) a named block of code (d) a screen size
  19. 19.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(40, 2));
  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(10) + fee(6));
  21. 21.🧰 Why write a function? (a) to reuse code (b) to make code longer (c) to hide errors (d) to slow the app
  22. 22.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Aman"));     (a) Aman (b) Welcome, name! (c) greet (d) Welcome, Aman!
  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 60;
    }
    show(fee(11) + fee(2));
  24. 24.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(5) + points(3));
  25. 25.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Riya"));     (a) Riya (b) Hello, Riya! (c) Hello, name! (d) greet
  26. 26.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(14));
  27. 27.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(10));
  28. 28.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(20, 2));
  29. 29.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(40, 3));
  30. 30.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Zoya"));     (a) Well done, Zoya! (b) greet (c) Well done, name! (d) Zoya
  31. 31.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(23));
  32. 32.🧰 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(5));
  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(4) + fee(9));
  34. 34.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(30, 6));
  35. 35.🧰 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(10));
  36. 36.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(80, 2));
  37. 37.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(5) + points(1));
  38. 38.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Meera"));     (a) Hello, Meera! (b) Meera (c) greet (d) Hello, name!
  39. 39.🧰 What does this code show?
    function greet(name) {
      return "Well done, " + name + "!";
    }
    show(greet("Aman"));     (a) greet (b) Aman (c) Well done, name! (d) Well done, Aman!
  40. 40.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(2) + points(1));

Answer key

  1. 500
  2. greet()
  3. 48
  4. Well done, Arjun!
  5. Hello, Kabir!
  6. 60
  7. Well done, Riya!
  8. 80
  9. Welcome, Zoya!
  10. 30
  11. Well done, Kabir!
  12. a parameter
  13. 100
  14. sends back a value
  15. 80
  16. 0
  17. 80
  18. a named block of code
  19. 80
  20. 40
  21. to reuse code
  22. Welcome, Aman!
  23. 60
  24. 90
  25. Hello, Riya!
  26. 28
  27. 30
  28. 40
  29. 120
  30. Well done, Zoya!
  31. 69
  32. 20
  33. 20
  34. 180
  35. 50
  36. 160
  37. 70
  38. Hello, Meera!
  39. Well done, Aman!
  40. 40

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