Convert first all terms into cm.i.e. 1575 cm, 1125cm, 765cm.Now whenever we need to calculate this type of question, we need to find the HCF.HCF of above terms is 255.
L.C.M. of 5,6,7,8 = 840. Required number is of the form 840k + 3 Least value of k for which (840k + 3) is divisible by 9 is k = 2. Required number = (840 X 2 + 3)=1683