Item

95% Confidenceinterval

Variation of estimated percentages

Cement

(27269.19, 28077.78)

(6.32, 9.48)

Hollowbrick

(25804.46, 26030.60)

(0.61, 1.49)

Terracotta block

(27279.87, 27593.32)

(6.36, 7.59)

Whitewash

(25933.25, 26173.28)

(1.11, 2.05)

Iron 10 mm

(26096.53, 26345.13)

(1.75, 2.72)

Iron 12 mm

(25953.13, 26412.15)

(1.19, 2.98)

Zinc

(26279.24, 26675.25)

(2.46, 4.01)

Grey hollowbrick

(26693.55, 27097.78)

(4.08, 5.65)

Hollowbrick “Hiper”

(26634.23, 26852.03)

(3.85, 4.70)

Iron 8 mm

(26147.91, 26513.05)

(1.95, 3.37)

Brick (special)

(25715.36, 25821.05)

(0.26, 0.68)

Iron 6 mm

(25661.82, 26329.46)

(0.06, 2.66)