A factory manufacture 120000 pencils daily. The pencils are cylindrical in shape each of leght 25 cm and circuference of base as 1.5 cm .Determine the cost of colouring the curved surface of the pencils manufactured in one day at ₹ 0.25 per `dm^(2)`

Explanation

Given ,pencil are cylindrical in shape.
Length of one pencil = 25 cm
and circumference of base = 1.5 cm
`rArr " "f= (1.5 xx 7)/(22 xx 2) = 0.2386 cm`
Now, curved surface area of one pencil `= 2 pi rh`
` = 2 xx (22)/(7) xx 0.2386 xx 25`
`= (26.46)/(7) = 37.49 cm^(2)" "[therefore 1 cm = (1)/(10) dm]`
`= 0.375 dm^(2)`
`therefore` Curved surface area of 120000 pencils `= 0.375 xx 120000 = 45000 dm^(2)`
Now, cost of colouring `1 dm^(2)` curved surface of the pencils manufactured in one day `= ₹0.05`
`therefore` Cost of colouring `45000 dm^(2)` cured surface `= ₹2250`