Determination of FM and percent of Silt and Clay?

Problem 1: Find FM and percent of Silt and Clay for the following data?
Exam Name: BPDB 2015, WASA 2014, BWDB 2013 

Sieve Size	#4	#8	#16	#30	#50	#100	#200	Pan
% of Reatain	0	1	4	12	43	2	2	4

Solution:

Sieve Size	% of Retain	Cumulative % of Retain	Percent of finer
#4	0	0	100
#8	1	1	99
#16	4	5	95
#30	12	17	83
#50	43	60	40
#100	2	62	38
#200	2	64	36
Pan	4	68	32

Sum of Cumulative percent for stand sieves =145
FM=145/100
      = 1.45

Percent of Silt and Clay =(36-32)%=4%
Answer: FM=1.45, Percent of Silt and Clay = 4%

---

Problem 2: Determine the FM for the following data of sand? Is it suitable for plastering or RCC work?  
Exam Name: RRI 2014 

Sieve Size	#4	#8	#16	#30	#40	#50	#100	200	Pan
% of Reatain	0	1	3	2	12	4	5	3	1

Solution:

Sieve Size	% of Retain	Cumulative % of Retain
#4	0	0
#8	1	1
#16	3	4
#30	2	6
#40	12	---
#50	4	10
#100	5	15
200	3	---
Pan	1	---

Sum of Cumulative percent for stand sieves =145
FM=36/100
      =0.36
 Answer: FM= 0.36,
 It is Suitable for plastering work

---