App Dev Worksheet: Functions

App development lesson 20: Functions · Set 574 · 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.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Riya")); (a) Welcome, Riya! (b) greet (c) Riya (d) Welcome, name!
2.🧰 What does return do in a function? (a) deletes the app (b) closes the screen (c) repeats the code (d) sends back a value
3.🧰 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(1));
4.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(2) + points(1));
5.🧰 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(4));
6.🧰 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(8) + fee(8));
7.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(10));
8.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Meera")); (a) Meera (b) greet (c) Welcome, Meera! (d) Welcome, name!
9.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(23));
10.🧰 What is a function? (a) a type of phone (b) a screen size (c) a named block of code (d) a list of colours
11.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(32));
12.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(3));
13.🧰 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(11) + fee(12));
14.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(6));
15.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Kabir")); (a) Well done, Kabir! (b) Kabir (c) Well done, name! (d) greet
16.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(70, 3));
17.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(5));
18.🧰 What does this code show?
function greet(name) {
return "Hi, " + name + "!";
}
show(greet("Aman")); (a) greet (b) Hi, name! (c) Aman (d) Hi, Aman!
19.🧰 In function tip(bill), what is bill? (a) an event (b) a loop (c) a parameter (d) a screen
20.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(0));
21.🧰 What does this code show?
function greet(name) {
return "Hi, " + name + "!";
}
show(greet("Arjun")); (a) Hi, Arjun! (b) Arjun (c) Hi, name! (d) greet
22.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(13));
23.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(70, 5));
24.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(3));
25.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(5) + points(5));
26.🧰 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(1) + fee(9));
27.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(6));
28.🧰 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(3));
29.🧰 Why write a function? (a) to slow the app (b) to reuse code (c) to hide errors (d) to make code longer
30.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(2) + points(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 50;
}
show(fee(7) + fee(10));
32.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Zoya")); (a) Well done, Zoya! (b) Zoya (c) Well done, name! (d) greet
33.🧰 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(3) + fee(1));
34.🧰 How do you run (call) a function called greet? (a) greet[] (b) #greet (c) run greet (d) greet()
35.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(36));
36.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(2) + points(3));
37.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(18));
38.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(25, 4));
39.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Meera")); (a) greet (b) Well done, Meera! (c) Well done, name! (d) Meera
40.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(1) + points(5));

Answer key

Welcome, Riya!
sends back a value
40
40
0
40
20
Welcome, Meera!
69
a named block of code
96
9
40
12
Well done, Kabir!
210
100
Hi, Aman!
a parameter
50
Hi, Arjun!
39
350
6
110
20
18
30
to reuse code
70
100
Well done, Zoya!
0
greet()
72
60
54
100
Well done, Meera!
70

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