Advertisements
Advertisements
प्रश्न
There are two cuboidal boxes as shown in the adjoining figure. Which box requires the lesser amount of material to make?
 |
 |
| (a) | (b) |
Advertisements
उत्तर
For this we find their areas -
(a) Length of the first box (l) = 60 cm
Width of first box (b) = 40 cm
Height of first box (h) = 50 cm
Total surface area of first box = 2(lb + bh + hl)
= 2(60 × 40 + 40 × 50 + 50 × 60)
= 2(2400 + 2000 + 3000)
= 2 × 7400
= 14800 cm2
(b) Length of the second box (l) = 50 cm
Width of second box (D) = 50 cm
Height of second box (h) = 50 cm
Total surface area of second box = 2(lb + bh + hl)
= 2(50 × 50 + 50 × 50 + 50 × 50)
= 2(2500 + 2500 + 2500)
= 2 × 7500
= 15000 cm2
Here the area of the first box is less. Hence, less material is required to make it.
APPEARS IN
संबंधित प्रश्न
Three equal cubes are placed adjacently in a row. Find the ratio of total surface area of the new cuboid to that of the sum of the surface areas of the three cubes.
A wooden bookshelf has external dimensions as follows: Height = 110 cm, Depth = 25 cm, Breadth = 85 cm in following figure. The thickness of the plank is 5 cm everywhere. The external faces are to be polished and the inner faces are to be painted. If the rate of polishing is 20 paise per cm2 and the rate of painting is 10 paise per cm2. Find the total expenses required for polishing and painting the surface of the bookshelf.
The dining-hall of a hotel is 75 m long; 60 m broad and 16 m high. It has five – doors 4 m by 3 m each and four windows 3 m by 1.6 m each. Find the cost of :
(i) papering its walls at the rate of Rs.12 per m2;
(ii) carpetting its floor at the rate of Rs.25 per m2.
The capacity of a rectangular tank is 5.2 m3 and the area of its base is 2.6 x 104 cm2; find its height (depth).
The curved surface area and the volume of a toy, cylindrical in shape, are 132 cm2 and 462 cm3 respectively. Find, its diameter and its length.
The length, breadth, and height of a rectangular solid are in the ratio 6 : 4 :3. If the total surface area is 1728 cm2. Find its dimensions.
The length and breadth of a cuboid are 20 cm and 15 cm respectively. If its volume is 2400 cm3, find its height.
Find the volume of wood used in making a closed box 22 cm by 18 cm by 14 cm, using a 1 cm thick wood. Also, find the cost of wood required to make the box at the rate of Rs. 5 per cm³ How many cubes of side 2 cm can be placed in the box?
How much sheet metal is required to make a closed rectangular box of length 1.5 m, breadth 1.2 m, and height 1.3 m?
