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             \ 06-Jan-2025  Bharat Arora   Proof-7             Reader’s Sign _______________________ Date __________





            As 360 is closer to 361 than to 324, so  360  is approximately equal to 19.

            Sometimes we have to find the square root of non-perfect squares up to certain decimal places.
            Let us find the square root of 5 up to two decimal places.

             We write 5 as 5.000000 (writing as many zeros as required to make three pairs of numbers in the
            decimal part).
                                     2.236
                                 2   5.00 00 00

                                   –4                                                 Remember
                               42    100                                  If we are asked to find the square root up
                                                                          to two decimal places, we should find the
                                     –84                                  square root up to 3 places and then round
                              443      1600                               off. Similarly, if it is asked to find the square
                                      –1329                               root up to three places, we should find it up
                                                                          to 4 places and then round off.
                             4466       27100
                                       –26796
                                          304

            Since, the digit at the third place is greater than 5, so we round up 2.236 to 2.24.
            \  5  = 2.236 ≈ 2.24
                                                      2
            Example 31: Find the square root of  4  up to two decimal places.
                                                      3
            Solution: We have

                               2     14     14     3     42     42
                             4    =      =     ×     =      =
                               3      3      3     3     9     3

                                      6.4807
                              6     42.00 00 00 00
                                 –36
                            124      600                                              Quick Check

                                    –496                                           Find the square root of the
                           1288     10400                                          following up to two decimal
                                   –10304                                          places.
                         12960          9600                                       1.  30        2.  4  1

                                    –     0                                                           2
                        129607          960000
                                       – 907249
                                             52751

                              42    6 4807
                                     .
            Thus,                 =         = 2.1602
                             3        3
                               2
            So,              4    = 2.16 (up to two decimal places).
                               3

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