Can anyone tel wat this is ??

This is two sided error & can be rectified by any of the following ways --

Method 1: Pass two journal entries --

               (I) Furniture A/c           Dr.  710

                       To Rohan                        710

                  (Being the reversal of sale of furniture)

               (II) Rohan                    Dr.  170

                       To Furniture A/c               170

                  (Being correction of sale of furniture entry passed before)

Method 2: One rectifying entry instead of the two --

                Furniture A/c             Dr.  540

                     To Rohan                         540

               (Being the rectifying entry paased for sale of furniture)

I would advise to suggest method 1 so that in case of any problem, entry may easily be traced.

sir here credit sale of old furniture to rohan for Rs 170 posted as Rs 710. posted means posting from original book to ledger account or what sir ????