App Dev Worksheet: Functions

App development lesson 20: Functions · Set 900 · 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 "Hi, " + name + "!";
}
show(greet("Riya")); (a) Hi, Riya! (b) Hi, name! (c) greet (d) Riya
2.🧰 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(2));
3.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(8));
4.🧰 In function tip(bill), what is bill? (a) a screen (b) an event (c) a loop (d) a parameter
5.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(80, 3));
6.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Riya")); (a) Hello, name! (b) Riya (c) Hello, Riya! (d) greet
7.🧰 Why write a function? (a) to slow the app (b) to reuse code (c) to hide errors (d) to make code longer
8.🧰 What is a function? (a) a type of phone (b) a screen size (c) a named block of code (d) a list of colours
9.🧰 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(11));
10.🧰 What does return do in a function? (a) closes the screen (b) sends back a value (c) deletes the app (d) repeats the code
11.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(100, 2));
12.🧰 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(11));
13.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Arjun")); (a) Arjun (b) Welcome, Arjun! (c) Welcome, name! (d) greet
14.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Aman")); (a) greet (b) Welcome, Aman! (c) Aman (d) Welcome, name!
15.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(2) + points(5));
16.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Meera")); (a) Well done, name! (b) Meera (c) greet (d) Well done, Meera!
17.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(75, 6));
18.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(40, 3));
19.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(26));
20.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(1) + points(3));
21.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Aman")); (a) greet (b) Aman (c) Hello, Aman! (d) Hello, name!
22.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(17));
23.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Kabir")); (a) Hello, Kabir! (b) greet (c) Kabir (d) Hello, name!
24.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(35, 5));
25.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(2));
26.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(9));
27.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(30));
28.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(3) + points(5));
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(8) + fee(10));
30.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(23));
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(8) + fee(2));
32.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(50, 3));
33.🧰 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(1));
34.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(70, 2));
35.🧰 How do you run (call) a function called greet? (a) run greet (b) #greet (c) greet() (d) greet[]
36.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(25));
37.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(45, 4));
38.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(15, 4));
39.🧰 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(1));
40.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(60, 5));

Answer key

Hi, Riya!
0
16
a parameter
240
Hello, Riya!
to reuse code
a named block of code
80
sends back a value
200
60
Welcome, Arjun!
Welcome, Aman!
80
Well done, Meera!
450
120
52
50
Hello, Aman!
34
Hello, Kabir!
175
70
18
90
90
100
69
50
150
30
140
greet()
75
180
60
30
300

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