Advertisements
Advertisements
Question
The cost of preparing the walls of a room 12 m long at the rate of Rs. 1.35 per square metre is Rs. 340.20 and the cost of matting the floor at 85 paise per square metre is Rs. 91.80. Find the height of the room.
Advertisements
Solution
Given that
Length of room = 12m.
Let height of room be ‘h’ m.
Area of 4 walls = 2 (l + b)x h
According to question
`⇒2(l+b)xxhxx1.35=340.20`
`⇒2(12+b)xxhxx1.35=340.20`
`⇒(12+b)xxh=(170.10)/1.35=126 .......(1)`
Also area of floor = l x b
`∴lxxbxx0.85=91.80`
`⇒12xxbxx0.85 = 91.80`
`⇒b=9m`
Substituting b= 9m in equation (1)
`⇒(12+9)xxh=126`
`⇒h=6m`
APPEARS IN
RELATED QUESTIONS
The length, breadth and height of a room are 5 m, 4 m and 3 m respectively. Find the cost of white washing the walls of the room and the ceiling at the rate of Rs 7.50 per m2.
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 water tank is 3 m long, 2 m broad and 1 m deep. How many litres of water can it hold?
A tank open at the top is made of iron sheet 4 m wide. If the dimensions of the tank are 12 m × 8 m × 6 m, find the cost of iron sheet at Rs 17.50 per metre.
If the sum of all the edges of a cube is 36 cm, then the volume (in cm3) of that cube is
A solid cuboid of metal has dimensions 24 cm, 18 cm, and 4 cm. Find its volume.
Find the volume of wood required to make a closed box of external dimensions 80 cm, 75 cm, and 60 cm, the thickness of walls of the box being 2 cm throughout.
A cuboid is 8 m long, 12 m broad and 3.5 high, Find its
(i) total surface area
(ii) lateral surface area
The length and breadth of a cuboid are 20 cm and 15 cm respectively. If its volume is 2400 cm3, find its height.
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?
