To solve this question quickly, first remove decimal by multiplying each term with 100,Then terms become 210, 105, 63Then HCF of above terms is 21, So Answer is 0.21
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
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