App Dev Worksheet: Functions

App development lesson 20: Functions · Set 886 · 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, name! (b) greet (c) Hi, Riya! (d) Riya
2.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(85, 6));
3.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(39));
4.🧰 What does return do in a function? (a) repeats the code (b) sends back a value (c) deletes the app (d) closes the screen
5.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Zoya")); (a) Welcome, name! (b) greet (c) Welcome, Zoya! (d) Zoya
6.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(3) + points(4));
7.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(55, 3));
8.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Riya")); (a) Well done, name! (b) greet (c) Riya (d) Well done, Riya!
9.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(9));
10.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(8));
11.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(90, 3));
12.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(70, 6));
13.🧰 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(5));
14.🧰 What is a function? (a) a screen size (b) a list of colours (c) a named block of code (d) a type of phone
15.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(65, 5));
16.🧰 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(5) + fee(3));
17.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(3) + points(1));
18.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(55, 4));
19.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(10, 2));
20.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(1) + points(1));
21.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Meera")); (a) greet (b) Meera (c) Welcome, name! (d) Welcome, Meera!
22.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(25, 4));
23.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Aman")); (a) Welcome, name! (b) Welcome, Aman! (c) greet (d) Aman
24.🧰 How do you run (call) a function called greet? (a) run greet (b) greet[] (c) greet() (d) #greet
25.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Zoya")); (a) Well done, name! (b) greet (c) Well done, Zoya! (d) Zoya
26.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(12));
27.🧰 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(12));
28.🧰 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(10) + fee(3));
29.🧰 In function tip(bill), what is bill? (a) a screen (b) a loop (c) an event (d) a parameter
30.🧰 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(11) + fee(7));
31.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(60, 2));
32.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(9));
33.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(34));
34.🧰 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(10));
35.🧰 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(10) + fee(11));
36.🧰 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(7));
37.🧰 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(7));
38.🧰 What does this code show?
function greet(name) {
return "Hi, " + name + "!";
}
show(greet("Aman")); (a) Hi, Aman! (b) greet (c) Hi, name! (d) Aman
39.🧰 Why write a function? (a) to make code longer (b) to reuse code (c) to hide errors (d) to slow the app
40.🧰 What number does this code show?
function triple(n) {
return n * 3;
}
show(triple(6));

Answer key

Hi, Riya!
510
117
sends back a value
Welcome, Zoya!
80
165
Well done, Riya!
27
16
270
420
40
a named block of code
325
40
50
220
20
30
Welcome, Meera!
100
Welcome, Aman!
greet()
Well done, Zoya!
36
40
60
a parameter
80
120
18
68
20
60
40
20
Hi, Aman!
to reuse code
18

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