Question

The standard qwerty keyboard has 47 keys that can place characters on the screen. Each of these keys can also display a second character by holding the shift key at the same time. How many bits would you need to encode everything that could be typed on this keyboard?

Answer 1

Answer:

7 bits.

Explanation:

In operating system, bits are used to hold or display the data. The combination of bits can be used to display the multiple items. For example, a simple bit can only show two different characters that would be mapped on either 0 or 1.

Similarly, two bits can store or hold four different characters using the combinations 00, 01, 10 and 11. In short, the total number encoded by a specific number of bits "n" can be calculated using $2^{n}$.

In this scenario, we have a total of 47 keys. In addition, each key can show a different character by holding shift key. Therefore, each key can show two different characters that makes 47 x 2 = 94 characters.

To show 94 characters, we need to find the bits using $2^{n}$.

Lets start with 5 bits.

$2^{5} = 32$,  32 < 94 that cannot fulfill our requirements.

$2^{6} = 64$, 64 < 94 that still cannot fulfill our requirements.

$2^{7} = 128$, 128 > 94 Therefore, 7 bits could be used to display 94 different characters.