Item

95% Confidenceinterval

Variation of estimated percentages

Cement

(27269.57, 28078.16)

(6.32, 9.48)

Hollow brick

(25804.41, 26030.55)

(0.61, 1.49)

Terracotta block

(27280.13, 27593.58)

(6.37, 7.59)

Hollow brick “Hiper”

(26634.06, 26851.86)

(3.85, 4.70)

Brick (special)

(25715.37, 25821.06)

(0.26, 0.68)