Advertisements
Advertisements
Question
An open box is made of wood 3 cm thick. Its external length, breadth and height are 1.48 m, 1.16 m and 8.3 m. Find the cost of painting the inner surface of Rs 50 per sq. metre.
Advertisements
Solution
Given
Length =1.48m=148cm.
Breath =1.16m =116 cm
Height = 8.3m = 83cm
Thickness of wood = 3cm
∴ inner dimensions:
Length (148 - 2 x 3)cm = 142cm
Breadth (116 - 2 x 3) cm = 110cm
Height= (83 - 3) cm = 80cm.
Inner surface area = 2 (l + b) + lb
`=2[(142)+100)80+142xx110cm^2]`
`2(252)[80]+142xx110cm^2=55,940cm^2`
`=559.40m^2`
Hence, cost of painting inner surface area
`=5,5940xxRs.50`
`=Rs.279.70`
APPEARS IN
RELATED QUESTIONS
A small indoor greenhouse (herbarium) is made entirely of glass panes (including base) held together with tape. It is 30 cm long, 25 cm wide and 25 cm high. What is the area of the glass?
The length of a hall is 18 m and the width 12 m. The sum of the areas of the floor and the
flat roof is equal to the sum of the areas of the four walls. Find the height of the hall.
Each edge of a cube is increased by 50%. Find the percentage increase in the surface area of the cube.
Ravish wanted to make a temporary shelter for his car by making a box-like structure with tarpaulin that covers all the four sides and the top of the car ( with the front face as a flap which can be rolled up). Assuming that the stitching margins are very small, and therefore negligible, how much tarpaulin would be required to make the shelter of height 2.5 m with
base dimensions 4 m × 3m?
How many persons can be accommodated in a big-hall of dimensions 40 m, 25 m, and 15 m; assuming that each person requires 5 m3 of air?
The height of a rectangular solid is 5 times its width and its length is 8 times its height. If the volume of the wall is 102.4 cm3, find its length.
If radii of two cylinders are in the ratio 4 : 3 and their heights are in the ratio 5: 6, find the ratio of their curved surfaces.
Opposite faces of a cuboid are ______ in area.
External dimensions of a closed wooden box are in the ratio 5:4:3. If the cost of painting its outer surface at the rate of Rs 5 per dm2 is Rs 11,750, find the dimensions of the box.
