App Dev Worksheet: Functions

App development lesson 20: Functions · Set 976 · 40 questions

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.

1. 1.🧰 What does this code show?
   function greet(name) {
     return "Hello, " + name + "!";
   }
   show(greet("Riya")); (a) Hello, name! (b) Riya (c) Hello, Riya! (d) greet
2. 2.🧰 What number does this code show?
   function total(price, qty) {
     return price * qty;
   }
   show(total(90, 6));
3. 3.🧰 Why write a function? (a) to reuse code (b) to hide errors (c) to slow the app (d) to make code longer
4. 4.🧰 What number does this code show?
   function triple(n) {
     return n * 3;
   }
   show(triple(5));
5. 5.🧰 What is a function? (a) a list of colours (b) a type of phone (c) a screen size (d) a named block of code
6. 6.🧰 What number does this code show?
   function triple(n) {
     return n * 3;
   }
   show(triple(26));
7. 7.🧰 What number does this code show?
   function double(n) {
     return n * 2;
   }
   show(double(9));
8. 8.🧰 What number does this code show?
   function triple(n) {
     return n * 3;
   }
   show(triple(29));
9. 9.🧰 What does this code show?
   function greet(name) {
     return "Hi, " + name + "!";
   }
   show(greet("Kabir")); (a) Kabir (b) Hi, Kabir! (c) greet (d) Hi, name!
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.🧰 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(4) + fee(11));
12. 12.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(2) + points(1));
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 30;
    }
    show(fee(8) + fee(10));
14. 14.🧰 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(1));
15. 15.🧰 What does this code show?
    function greet(name) {
      return "Welcome, " + name + "!";
    }
    show(greet("Riya")); (a) Welcome, Riya! (b) Welcome, name! (c) Riya (d) greet
16. 16.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(4) + points(3));
17. 17.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(40));
18. 18.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(100, 3));
19. 19.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(36));
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 30;
    }
    show(fee(5) + fee(10));
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 40;
    }
    show(fee(12) + fee(12));
22. 22.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(14));
23. 23.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(2) + points(5));
24. 24.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Aman")); (a) Hello, name! (b) greet (c) Aman (d) Hello, Aman!
25. 25.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Kabir")); (a) Kabir (b) Hello, Kabir! (c) Hello, name! (d) greet
26. 26.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(39));
27. 27.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(10));
28. 28.🧰 How do you run (call) a function called greet? (a) greet() (b) greet[] (c) run greet (d) #greet
29. 29.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(5) + points(3));
30. 30.🧰 What number does this code show?
    function points(stars) {
      return stars * 10 + 5;
    }
    show(points(1) + points(5));
31. 31.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(15, 6));
32. 32.🧰 What number does this code show?
    function double(n) {
      return n * 2;
    }
    show(double(3));
33. 33.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(9));
34. 34.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(21));
35. 35.🧰 What does this code show?
    function greet(name) {
      return "Hello, " + name + "!";
    }
    show(greet("Arjun")); (a) Hello, Arjun! (b) Hello, name! (c) Arjun (d) greet
36. 36.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(31));
37. 37.🧰 What number does this code show?
    function triple(n) {
      return n * 3;
    }
    show(triple(27));
38. 38.🧰 What number does this code show?
    function total(price, qty) {
      return price * qty;
    }
    show(total(80, 4));
39. 39.🧰 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(9));
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 20;
    }
    show(fee(2) + fee(12));

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