App Dev Worksheet: Functions

App development lesson 20: Functions · Set 488 · 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 40;
}
show(fee(4) + fee(6));
2.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Zoya")); (a) Zoya (b) Hello, name! (c) greet (d) Hello, Zoya!
3.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(2) + points(3));
4.🧰 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(1) + fee(3));
5.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(1) + points(0));
6.🧰 What does return do in a function? (a) repeats the code (b) sends back a value (c) closes the screen (d) deletes the app
7.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Arjun")); (a) Arjun (b) Hello, name! (c) Hello, Arjun! (d) greet
8.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(20, 5));
9.🧰 In function tip(bill), what is bill? (a) an event (b) a parameter (c) a screen (d) a loop
10.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Riya")); (a) Hello, Riya! (b) greet (c) Riya (d) Hello, name!
11.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(20, 3));
12.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(2) + points(4));
13.🧰 Why write a function? (a) to hide errors (b) to slow the app (c) to make code longer (d) to reuse code
14.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Meera")); (a) Meera (b) Welcome, Meera! (c) greet (d) Welcome, name!
15.🧰 How do you run (call) a function called greet? (a) run greet (b) #greet (c) greet() (d) greet[]
16.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(4));
17.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(1) + points(5));
18.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(3) + points(4));
19.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(95, 5));
20.🧰 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(11));
21.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(25, 6));
22.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(30, 5));
23.🧰 What is a function? (a) a screen size (b) a named block of code (c) a list of colours (d) a type of phone
24.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(18));
25.🧰 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));
26.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(3) + points(1));
27.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(100, 2));
28.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(6));
29.🧰 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(9));
30.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Zoya")); (a) greet (b) Well done, name! (c) Zoya (d) Well done, Zoya!
31.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(40));
32.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Meera")); (a) Meera (b) Hello, Meera! (c) Hello, name! (d) greet
33.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(23));
34.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(60, 5));
35.🧰 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(6) + fee(9));
36.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(90, 2));
37.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(1) + points(4));
38.🧰 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(3));
39.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Aman")); (a) Hello, Aman! (b) Hello, name! (c) greet (d) Aman
40.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(100, 3));

Answer key

40
Hello, Zoya!
60
0
20
sends back a value
Hello, Arjun!
100
a parameter
Hello, Riya!
60
70
to reuse code
Welcome, Meera!
greet()
90
70
80
475
80
150
150
a named block of code
36
40
50
200
18
40
Well done, Zoya!
80
Hello, Meera!
69
300
120
180
60
50
Hello, Aman!
300

Free app development lessons, practice and worksheets at talentjr.in/app-development-for-students