how many bricks of length 25 CM breadth 9 cm and thickness 7.5 CM are needed to build a Wall of length 5 metre breadth 27 and height 2.5m
Answers
Answer:
4320
Step-by-step explanation:
Both the brick and the wall are in the shape of a cuboid.
Volume of a cuboid of length l, breadth b and height h =l×b×h.
Considering all the measures in cm, number of bricks required =
Volumeofonebrick
Volumeofthewall
=
25×12.5×7.5
1500×180×37.50
=4320
Step-by-step explanation:
Volume of a cuboid =(Length×Breadth×Height) cubic units
Total surface area =2(lb+bh+lh) sq units
Lateral surface area =[2(l+b)×h] sq units
(i) Length = 22 cm, breadth = 12 cm, height = 7.5 cm
Volume =(Length×Breadth×Height) = (22×12×7.5)=1980
Total surface area =2(lb+bh+lh)= 222×12+22×7.5+12×7.5=2264+165+90=1038 cm2
Lateral surface area =2l+b×h=222+12×7.5=510 cm2
(ii) Length = 15 m, breadth = 6 m, height = 9 dm = 0.9 m
Volume =(Length×Breadth×Height) = (15×6×0.9)=81 m3
Total surface area=2(lb+bh+lh) = 215×6+15×0.9+6×0.9=290+13.5+5.4=217.8 m2
Lateral surface area =2l+b×h=215+6×0.9=37.8 m2
(iii) Length = 24 m, breadth = 25 cm = 0.25 m, height = 6 m
Volume =(Length×Breadth×Height) = (24×0.25×6)=36 m3
Total surface area=2(lb+bh+lh) = 224×0.25+24×6+0.25×6=26+144+1.5=303 m2
Lateral surface area =2l+b×h=224+0.25×6=291 m2
(iv) Length = 48 cm = 0.48 m, breadth = 6 dm = 0.6 m, height = 1 m
Volume =(Length×Breadth×Height) = (0.48×0.6×1)=0.288 m3
Total surface area =2(lb+bh+lh)= 20.48×0.6+0.48×1+0.6×1=20.288+0.48+0.6=2.736 m2
Lateral surface area =2l+b×h=20.48+0.6×1=2.16 m2