Question

Rahul walks 2 by 3 km from a place P towards east and then from there 15 by 6 km towards west what is the what is his position now from p by using rational numbers

Answer 1

Each tick on the number line represents 1/6 km.  From point P, move 4 ticks to the right (2/3 = 4/6 km east) to point a. 
 From point a, move 15 ticks to the left (15/6 km west) to point b.  You are at 4/6 - 15/6 = -7/6, or 7/6 (1 1/6) km west of point P.                                        b                          P              a   
                                       B                                      P            A
    West <--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|--|-->    EAST                                                            ------------->