Question

from a rope 20m long, rohit cut off 3 pieces of 2 2/3 m each and Nandita cut off 2 pieces of 4 1/2 m each. what length of the rope is left?

Answer 1

length of rope left - total-(length rohit cut+length nandita cut)
                             =20m-(3*2 2/3 + 2*4 1/2)m
                             =20m-(3*8/3 + 2*9/2)m
                             =20m-(24/3+18/2)m
                             LCM of 2 and 3 is 6
                             =20m-{(24/3=48/6)+(18/2=54/6}m
                             =20m-(48/6+54/6)m
                             =20m-(102/6)m
                             =20m-17m
length of rope left =3m