Determine the approximate proportion of dry cement mortar required for brick work with bricks of nominal size 19 cm x 9 cm x 9 cm, with 18 % extra for frog filling and wastage is : (assume 1 m3 of wet mortar = 1.3 m3 of dry mortar):
1
41%
2
35.3%
3
26.7%
4
32.5%