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Take Off                                                    Century   #Critical thinking
                                                                                             21 st
                                                                                             Skills  #Productivity & Accountability
                      Solve the following sums. Also note the time you took to solve each of them.
                      1.  345678 – 789 =                                (Time taken to solve:          )
                      2.  567 x 55 =                                    (Time taken to solve:          )
                      3.  100 x 9 + 890 – 67 =                          (Time taken to solve:          )

                      4.  22/11 + 20 – 4 x 2 =                          (Time taken to solve:          )
                      Do you know how computer solves these sums and how quickly it does it? Let's find out in this chapter.





                A computer takes data from a user and produces result as information. Although the words 'data and
                information'  are often used interchangeably, but there is an important distinction between the two
                words. In a strict sense, data refers to the raw, unorganised facts and figures (data) that computers
                process to produce meaningful information.

                From an early age, we are introduced to the concept of numbers and counting. Toddlers learn at an
                early age that they can carry two cookies, one in each hand. Kindergarteners start counting by twos and
                fives. Invariably, we use the decimal number system. Our number system is based on 10, most likely
                because we have tendency to count using our ten fingers. Let us learn more about the number system.


                     WHAT IS A NUMBER SYSTEM?


                A number system is a systematic way of representing numbers to describe quantities. There are many
                number systems in existence. Consider a digital clock. Digital clocks have 24 hours, each hour has 60
                minutes. Each minute is in turn has 60 seconds. When you learnt to count, you used the numbers, like
                1, 2, 3, etc. Similarly, computers also have their own number system, known as the binary number
                system. The digital computer represents all kinds of data and information like audio, graphics, video,
                text and numbers in binary form.
                The total number of digits used in a number system is called its base or radix. Therefore, when
                someone says that he/she is working with number system of radix 2, it means base 2, i.e., binary
                number system. The base is written after the number as subscript such as (512) . In this example,
                                                                                                     10
                the number 10 is written as the subscript to express the number 512 in decimal number system.


                          Factbot


                       The numerical digits, we use today, i.e., 1, 2 and 3 are based on the Hindu-Arabic numeral system.
                      Different names for the number 0 include zero, nought, naught, nil, zilch and zip.




                There are four types of number systems, which are as follows:
                1.  Decimal number system           2.  Binary number system

                3.  Octal number system             4.  Hexadecimal number system




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