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
Find the volume of a cuboid whose length = 15 cm, breadth = 2.5 dm, height = 8 cm.
A cuboidal block of solid iron has dimensions 50 cm, 45 cm and 34 cm. How many cuboids of size 5 cm by 3 cm by 2 cm can be obtained from this block? Assume cutting causes no wastage.
How many planks each of which is 3 m long, 15 cm broad and 5 cm thick can be prepared from a wooden block 6 m long, 75 cm broad and 45 cm thick?
Volume of a cuboid is 12 cm3. The volume (in cm3) of a cuboid whose sides are double of the above cuboid is
A closed rectangular box is made of wood of 1.5 cm thickness. The exterior length and breadth are respectively 78 cm and 19 cm, and the capacity of the box is 15 cubic decimeters. Calculate the exterior height of the box.
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.
Find the height of the cylinder whose radius is 7 cm and the total surface area is 1100 cm2.
The dimensions of a hall is 10 m × 9 m × 8 m. Find the cost of white washing the walls and ceiling at the rate of ₹ 8.50 per m2
