App Dev Worksheet: Functions

App development lesson 20: Functions · Set 670 · 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 number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(3));
2.🧰 How do you run (call) a function called greet? (a) greet[] (b) run greet (c) greet() (d) #greet
3.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(2) + points(1));
4.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(2));
5.🧰 What does return do in a function? (a) sends back a value (b) repeats the code (c) closes the screen (d) deletes the app
6.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Riya")); (a) greet (b) Well done, Riya! (c) Well done, name! (d) Riya
7.🧰 What is a function? (a) a named block of code (b) a screen size (c) a type of phone (d) a list of colours
8.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Riya")); (a) Riya (b) Hello, name! (c) Hello, Riya! (d) greet
9.🧰 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(12) + fee(3));
10.🧰 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(4) + fee(4));
11.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Zoya")); (a) Hello, name! (b) greet (c) Hello, Zoya! (d) Zoya
12.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(15, 4));
13.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(35, 3));
14.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(1) + points(0));
15.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(3) + points(0));
16.🧰 What does this code show?
function greet(name) {
return "Welcome, " + name + "!";
}
show(greet("Riya")); (a) Welcome, Riya! (b) Riya (c) Welcome, name! (d) greet
17.🧰 In function tip(bill), what is bill? (a) an event (b) a parameter (c) a loop (d) a screen
18.🧰 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(2) + fee(10));
19.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(30, 2));
20.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(50, 6));
21.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Zoya")); (a) Well done, Zoya! (b) greet (c) Zoya (d) Well done, name!
22.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(3));
23.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(60, 5));
24.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(5) + points(3));
25.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(5) + points(0));
26.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(4) + points(5));
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(5) + fee(9));
28.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(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 40;
}
show(fee(11) + fee(11));
30.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(9));
31.🧰 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(6) + fee(11));
32.🧰 What number does this code show?
function total(price, qty) {
return price * qty;
}
show(total(15, 6));
33.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(2) + points(2));
34.🧰 What does this code show?
function greet(name) {
return "Hello, " + name + "!";
}
show(greet("Kabir")); (a) greet (b) Hello, Kabir! (c) Kabir (d) Hello, name!
35.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(1) + points(1));
36.🧰 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(8) + fee(7));
37.🧰 What number does this code show?
function points(stars) {
return stars * 10 + 5;
}
show(points(3) + points(3));
38.🧰 What number does this code show?
function double(n) {
return n * 2;
}
show(double(23));
39.🧰 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(9));
40.🧰 What does this code show?
function greet(name) {
return "Well done, " + name + "!";
}
show(greet("Kabir")); (a) Kabir (b) greet (c) Well done, Kabir! (d) Well done, name!

Answer key

80
greet()
40
70
sends back a value
Well done, Riya!
a named block of code
Hello, Riya!
60
0
Hello, Zoya!
60
105
20
40
Welcome, Riya!
a parameter
50
60
300
Well done, Zoya!
6
300
90
60
100
40
8
80
18
60
90
50
Hello, Kabir!
30
80
70
46
40
Well done, Kabir!

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