Lesson Objectives:
To be able to:
- Define the terms bit, nibble, byte, kilobyte etc …
- Understand that data needs to be converted into a binary format
to be processed by a computer
- To be able to convert positive binary to decimal and vice versa
Starter
Q1) What is binary?
Q2) Why do computers use binary?
The table below shows measurements for data or you can think of it as capacity. Use Google
to help you fill the table below:
Bit
Nibble
8 bits
1024 bytes
1024 kilobytes
1024 megabyte
1024 gigabyte
A bit is equal to a 1 or 0
4 bits
1 kilobyte
Binary Conversion
Decimal
As humans, we use a numbering system called decimal. This numbering system is base 10
which means that each time the number is getting bigger by x10.
10^3
1000
10^2
100
10^1
10
10^0
1
Note: This is the decimal / denary numbering system that we use.
Binary
Computers use a numbering system called binary. This numbering system is base 2. The
reason why computers use binary and base 2 is that it is easier to represent. For example we
can represent a positive and negative charge quite easily using circuits.
1 = on or positive
0 = off or negative
Conversion guide Decimal to binary
The number: 5
1. Draw your 8 bits binary number column
128
0
2.
3.
4.
5.
6.
7.
8.
9.
64
0
32
0
16
0
8
0
4
1
2
0
1
1
Now we are going to ask, will the number 128 fit into 5? If it doesn’t we put a 0
Will 64 fit into fit into 5? It doesn’t put a 0
32? No, 0
16? No, 0
8? No, 0
4? Yes 5 – 4 = 1
2? No,
Will 1 fit into 1, yes but a 1
Use the example above to complete the binary conversion below.
Worksheet
Binary Conversion Cross-Number 1
1
2
3
5
7
6
8
11
9
12
16
18
4
10
14
13
15
17
19
20
Convert denary numbers to binary and binary numbers to denary.
If a number consists of 1s and 0s, assume it is binary. Otherwise assume it is denary.
Across
1.
254
5.
5
7.
9.
1011
111101
11.
14.
16.
20.
101001
110011
6
131
Down
1.
13
2.
3.
10010
1111000
4.
5.
6.
8.
10.
12.
13.
15.
17.
18.
19.
1100
1010
10000
1110
1111
3
111100
9
4
1010000
11110
Programming
Task 1
Every variable has a given data type. You need to explain the different types of variable and
what they are used for. The most common data types are:
String - ?
Integer ?
Float - ? Also known as real numbers
Boolean –
In some languages we have to tell the computer what data type a variable is going to be.
Python, on the other hand, is able to decide the data type of the variable according to what
value it is first given (or to use the correct term what it is initialised with). This can cause
problems when we try to do something with the wrong data type.
Task 2
Create a program that uses if statements and operators to test conditions. You could make a
program that will ask the person their age and then say whether or not the can purchase learn
to drive a car.
Task 3 (15)
Create a program that will ask the user for the current year and the year she was born. The
program should then workout her age i.e. how old she is. Once we know how old she is, we
should then be able to find out how many days she has lives, hours, minutes and even
seconds.
Clues
current = int(input("Enter current year"))
born = ?
days = age * 365
print("The value is " +
str(days))
Task 4 (15)
We can store text in variables and we can then manipulate that text. To do this we use
something called string method. I have put an example below, it is your job to try all of them
and explain what they do and find other examples online.
Name = “Bob”
Print(Name.upper())
The output: BOB
String
method
Description of what it does
lower()
upper()
title()
swapcase()
capitalize()
Can you remember what concatenation is? If not, do a quick search online and make a note of
it.
Task 5 - Restaurant Tip
Write a program.
Two people eat dinner at a restaurant and want to split the bill.
The total comes to £100 and they want to leave a 15% tip. How much should each person
pay?
Harder: make the program ask how many people there are, what percentage the tip should be
and how much the bill comes to.
Save this as Restaurant tip.
Task 6 - Restaurant Tip
The grade boundaries for a test are:
U-0
D – 40
C – 50
B – 60
A – 70
Write a program that asks for a mark and then says what grade it is worth.