INDEX of fineness and coarseness of the aggregates. It is defined as the SUMMATION of cumulative % of aggregates retained over different sieve ranging from 150μ to 80 mm divided by a constant parameter that is generally taken to be 100.Fineness modulus = \(\frac{{\% \;AMOUNT\;of\;COARSE\;aggregate\;retained}}{{100}} = \frac{{694.5}}{{100}} = 6.945\)