# Computer and decimal number

For most purposes, however, binary values are converted to or from the equivalent decimal values for presentation to or input from humans; computer programs express literals in decimal by default. Both computer hardware and software also use internal representations which are effectively decimal for storing decimal values and doing arithmetic. Often this arithmetic is done on data which are encoded using some variant of binary-coded decimal  especially in database implementations, but there are other decimal representations in use such as in the new IEEE Standard for Floating-Point Arithmetic. This is especially important for financial calculations, e. How to count to on two hands Video transcript Let's see if we can get some experience converting from a decimal representation to a binary representation.

Let's start with the fairly straightforward example with a fairly low number. Let's see if we can convert the number 13 in decimal to binary. And I encourage you to pause the video, and try to work through it out on your own.

So I'm assuming you had a go at it. So the key here is to see if you can deconstruct the number 13 as the sum of powers of two. And then it becomes very straightforward to represent it in binary. Because in binary, you're essentially saying, well what powers of two do you need to make up this number. So let's just write the powers of two here, just to remind ourselves.

And I'll go until we go right above So two to the zero is equal to one, Two to the first is equal to 2.

## How to convert a decimal number to ASCII representation - Computer Science Stack Exchange

Two squared is equal to four. Two to the third is equal to eight. Two to the fourth is equal to So now, I'm above 13, so I have all the powers of two that I need to construct So what's the largest power of two, that is less than or equal to 13?

Well, 16's too large, well it would be eight. So I could rewrite 13 as eight plus five. Now five is not a power of two, so I have to keep deconstructing that. What's the largest power of two, that is less than or equal to five? We see it right over here, it's four. So let me rewrite that, it's eight plus, instead of writing five, I'll write four plus one, and then the good thing is at one as a power of two we already see is the largest power of two that is less than or equal to it is one.

This already is a power of two.

## Conversion from Binary to Decimal

So I now have rewritten this as the sum of powers of two.Binary code, code used in digital computers, based on a binary number system in which there are only two possible states, off and on, usually symbolized by 0 and 1.

Whereas in a decimal system, which employs 10 digits, each digit position represents a power of 10 (, 1,, etc.), in a binary system each digit position represents a power of 2 (4, 8, 16, etc.). Any double-precision floating-point number can be identified with at most 17 significant decimal digits.

This means that if you convert a floating-point number to a decimal string, round it (to nearest) to 17 digits, and then convert that back to floating-point, you will recover the original floating-point number.

decimal number has five digits, we would say that the binary number is a five-bit number. The point: All data in a computer is represented in binary. The pictures of your last vacation stored on your hard drive—it’s all bits.

## Decimal to Binary Conversion using C program

The YouTube video of the cat . Move the decimal place to the right to create a new number from 1 up to So, N = Determine the exponent, which is the number of times you moved the decimal. Great method to convert mentally from decimal to binary. Other methods mentioned works in a reverse order, i.e. when one finishes the division by 2, that last remainder is the 1st digit from left side in the binary number (so difficult to do mentally).

The binary number system is an alternative to the decimal (base) number system that we use every day. Binary numbers are important because using them instead of the decimal system simplifies the design of computers and related technologies.

Binary to Decimal in Computers - Stack Overflow