Page 66 - Computer Science Class 11 With Functions
P. 66

g.  (101.01) =(  ?   ) 2
                        8
              h.  (420)  = (  ?   )
                     10      2
         Ans.  a.  (710) 8
              b.  (6A) 16
              c.  (57.625) 10
              d.  (163.6875) 10
              e.  (47.CCC) 16
              f.  (10101111)
                          2
              g.  (1000001.000001)
                                2
              h.  (110100100) 2

           6.  The following data is encoded in ASCII code. Use ASCII table to express the data symbolically.
              1011010         0110100         1010101
         Ans.  ASCII Code:       1011010         0110100       1010101

               Decimal Equivalent:   90           52              85
               Character:           Z              4              U
              Equivalent characters for the given code are : Z4U
           7.  Give binary representation for the word 'CoDe' using ASCII encoding scheme.
         Ans.  Character:             C            o           D            e

              ASCII Code in decimal:   67         111          68          101
              Binary Equivalent:    1000011     1101111     1000100      1100101
              Equivalent ASCII code is 1000011110111110001001100101


               Case Based Questions


           1.  Yuvika has always loved solving sums in mathematics. But she has always used the decimal number system, which uses the
              symbols - 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. Recently, she came to know about binary, octal, and hexadecimal number systems.
              She wants to know the different symbols that are used in these number systems. Write down the same for Yuvika.
         Ans.  Binary - 0 and 1
              Octal - 0,   1,   2,   3,   4,   5,   6,   and 7
              Hexadecimal - 0,   1,   2,   3,   4,   5,   6,   7,   8,   9,   A,   B,   C,   D,   E,   F

           2.  Gurmeet is a student of class XI. He has been assigned the task of explaining to his classmate why the decimal number
              system is a positional number system. Help him to complete his task.
         Ans.   A number system is positional if the position of a symbol in the representation of the number defines its value. In the case
              of a decimal number system, every symbol is assigned a value according to the position at which it is placed. For example,
              in the numbers 62, 23, and 249, the symbol 2 denotes the values two, twenty, and two hundred, respectively. Thus, the
              decimal number system is a positional number system.
           3.  Richa is learning about the decimal number system. She knows that every symbol in a number is represented by a value,
              known as face value. But, she is not clear about the place value of a symbol within a number. Explain to her with an
              example.
         Ans.  In a decimal number system, the value of a digit within a number depends on the position of the digit. For example,
                                                                     0
                 the right-most digit is called the one’s digit or unit digit (value 10  = one).
                                                                       1
                 the second digit from the right end is called the tens digit (value 10  =ten).
                                                                         2
                 the third digit from the right end is called the hundreds digit (value 10  = hundred), and so on.
              Now, consider the number 2376. In this number, the place values of different digits are as follows:
                 Digit 6 represents 6 units (6 × 1)


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