Question

Three person's step off together from a point their steps measure 40 cm 42 cm 45 cm respectively at what distance will they be together again if their speeds are same

Answer 1

lcm of 40,45,42

40=5*2*2*2

45=5*3*3

42=2*3*7

therefore,

(40,42,45)=5*2*2*3*3*2*7*5

=25*8*21

=4200

after 4200 of distance they will start the step together.