App Dev Worksheet: Functions

App development lesson 20: Functions · Set 29 · 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.

NameDateTime takenScore ___ / 40

1.🧰 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(9) + fee(1));
2.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(1) + points(2));
3.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(10, 5));
4.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(11));
5.🧰 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(7) + fee(10));
6.🧰 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(2));
7.🧰 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(2) + fee(3));
8.🧰 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(4));
9.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(5) + points(0));
10.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(50, 6));
11.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(26));
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(12) + fee(7));
13.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(80, 4));
14.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(90, 4));
15.🧰 In function tip(bill), what is bill? (a) an event (b) a parameter (c) a screen (d) a loop
16.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(25));
17.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(95, 5));
18.🧰 How do you run (call) a function called greet? (a) greet[] (b) run greet (c) greet() (d) #greet
19.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(9));
20.🧰 What does return do in a function? (a) closes the screen (b) repeats the code (c) deletes the app (d) sends back a value
21.🧰 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(4));
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(12) + fee(7));
23.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Riya")); (a) greet (b) Riya (c) Welcome, Riya! (d) Welcome, name!
24.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(19));
25.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Arjun")); (a) Arjun (b) Well done, Arjun! (c) Well done, name! (d) greet
26.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Meera")); (a) Well done, Meera! (b) Well done, name! (c) greet (d) Meera
27.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(31));
28.🧰 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(12) + fee(4));
29.🧰 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(9));
30.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(85, 4));
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(3) + fee(9));
32.🧰 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(1));
33.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(1));
34.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(0));
35.🧰 What is a function? (a) a screen size (b) a list of colours (c) a named block of code (d) a type of phone
36.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(40, 3));
37.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(70, 3));
38.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Aman")); (a) Hello, name! (b) Hello, Aman! (c) greet (d) Aman
39.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Kabir")); (a) Welcome, name! (b) Welcome, Kabir! (c) greet (d) Kabir
40.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(5) + points(2));

Answer key

20
40
50
33
60
0
0
50
60
300
78
80
320
360
a parameter
50
475
greet()
18
sends back a value
60
60
Welcome, Riya!
38
Well done, Arjun!
Well done, Meera!
93
20
50
340
20
0
60
50
a named block of code
120
210
Hello, Aman!
Welcome, Kabir!
80

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