Advertisements
Advertisements
Question
Find the cost of sinking a tubewell 280 m deep, having diameter 3 m at the rate of Rs 3.60 per cubic metre. Find also the cost of cementing its inner curved surface at Rs 2.50 per square metre.
Solution
Given data is as follows:
Height of the tube well = 280 m
Diameter = 3 m
Rate of sinking the tube well = Rs.3.60/m3
Rate of cementing = Rs.2.50/m2
Given is the diameter of the tube well which is 3 meters. Therefore,
`r = 3/2`m
Volume of the tube well = `pir^2h`
= `22/7 xx 3/2 xx3/2xx280`
= 1980 m2
Cost of sinking the tube well = Volume of the tube well × Rate for sinking the tube well
=1980 × 3.60
= Rs. 7128
Curved surface area = `2pirh`
= `2 xx 22/7 xx 3/2 xx 280 `
=2640 m2
Cost of cementing = `"Curved Surface Area " xx " Rate of cementing"`
= 2640 × 2.50
= Rs.6600
Therefore, the total cost of sinking the tube well is Rs.7128 and the total cost of cementing its inner surface is Rs.6600.
APPEARS IN
RELATED QUESTIONS
The circumference of the base of a cylinder is 88 cm and its height is 15 cm. Find its curved surface area and total surface area.
A solid cylinder has a total surface area of 231 cm2. Its curved surface area is \[\frac{2}{3}\] of the total surface area. Find the volume of the cylinder.
What length of a solid cylinder 2 cm in diameter must be taken to recast into a hollow cylinder of length 16 cm, external diameter 20 cm and thickness 2.5 mm?
How many litres of water flow out of a pipe having an area of cross-section of 5cm2 in one minute, if the speed of water in the pipe is 30 cm/ sec?
If the height of a cylinder is doubled, by what number must the radius of the base be multiplied so that the resulting cylinder has the same volume as the original cylinder?
Curved surface area of a cylinder is 1980 cm2 and radius of its base is 15 cm. Find the height of the cylinder. (π = `22/7`)
In the example given below, the radius of the base of a cylinder and its height is given. Then find the curved surface area and total surface area.
r = 7 cm, h = 10 cm
A solid iron cylinder has total surface area of 1848 sq.m. Its curved surface area is five – sixth of its total surface area. Find the radius and height of the iron cylinder.
If the radius of a cylinder is doubled and its curved surface area is not changed, the height must be halved.
In the example given below, the radius of the base of a cylinder and its height is given. Then find the curved surface area and total surface area.
r = 4.2 cm, h = 14 cm
