Advertisements
Advertisements
प्रश्न
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
उत्तर
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
संबंधित प्रश्न
A 4 cm edge cube is cut into 1 cm edge cubes. Calculate the total surface area of all the small cubes.
The central hall of a school is 80 m long and 8 m high. It has 10 doors each of size 3 m × 1.5 m and 10 windows each of size 1.5 m × 1 m. If the cost of white-washing the walls of the hall at the rate of Rs 1.20 per m2 is Rs 2385.60, fidn the breadth of the hall.
The dimensions of a rectangular box are in the ratio of 2 : 3 : 4 and the difference between the cost of covering it with sheet of paper at the rates of Rs 8 and Rs 9.50 per m2 is Rs. 1248. Find the dimensions of the box.
If the perimeter of each face of a cube is 32 cm, find its lateral surface area. Note that four faces which meet the base of a cube are called its lateral faces.
If each edge of a cuboid of surface area S is doubled, then surface area of the new cuboid is
The area of the floor of a room is 15 m2. If its height is 4 m, then the volume of the air contained in the room is
If A1, A2, and A3 denote the areas of three adjacent faces of a cuboid, then its volume is
The sum of the radius and the height of a cylinder is 37 cm and the total surface area of the cylinder is 1628 cm2. Find the height and the volume of the cylinder.
The floor of a rectangular hall has a perimeter 250 m. If the cost of painting the four walls at the rate of ₹ 10 per m2 is ₹ 15,000, find the height of the hall.
The surface area of a cuboid formed by joining face to face 3 cubes of side x is 3 times the surface area of a cube of side x.
