Binary Calculations: Computer Science OCR: GCSE (9:1)

Binary

Data format that can be represented by electrical voltages, which can then be processed by logic gates in the computer

Decimal

Also known as denary, the numbers we use in everyday life, which cannot be processed by the computer

Encoding

Converting data into a binary format so that that it can be stored and processed. ASCII and JPEG are both examples

Logic gate

The basic building block of digital computers, it processes only 0s and 1s, which is why we use binary to encode all data

Capacity

The maximum number of bytes a storage device can hold. Usually measured in MB, GB, TB or PB.

File size

The size of a file in bytes, MB, GB etc. Adding up all the file sizes we want to store gives us the capacity we need

60

Number of MB needed to store 600 documents of average size 100KB

30

Number of MB needed to store 60 sound files of 500KB each

80

A videographer stores 500MB of video every day. Her hard drive has 40GB free. How many days until she needs to buy a new drive (or archive some files)?

40

A musician records a new song using 6.4MB every week. How many songs can she store on a USB memory stick with a capacity of 256MB?

72

A text file stores one character in every byte. A document contains 12,000 characters. If I make six copies, how many Kilobytes is that altogether?

84

A CCTV system records constantly to hard disk at a rate of 500MB every hour. To record a whole week of video before overwriting, how big must the hard drive be, in GB?

360

A school stores all student data on their server. An average student has around 200MB of files, and there are 1200 students in the school. Providing enough space for the current students, and then allowing for 50% growth, what capacity storage device is needed, in GB?

1280

An SD card is labelled "32GB". How many high-resolution photo files of size 25MB can it store?