A man donates 10 aluminium buckets to an orphanage . A bucket made of aluminium is of h=20cm and has its upper and lower end of r=36cm and 21 cm . Find the cost of preparing 10 buckets if the cost of aluminium is rs 42 per 100 cm sq

Asked by thunderboyshubharth2005 | 13th Mar, 2021, 01:54: PM

Expert Answer:

Bucket in the shape of Frustum of a cone.
Given: r = 21 cm, R = 36 cm, h = 20 cm
Surface area of one bucket equals straight pi open parentheses straight r plus straight R close parentheses straight l plus πr squared where r is radius of bottom circular surface, R is radius of top surface, h is height and l is slant height given by straight l equals square root of open parentheses straight R minus straight r close parentheses squared plus straight h squared end root
Surface area of one bucket equals straight pi open parentheses 36 plus 21 close parentheses square root of open parentheses 36 minus 21 close parentheses squared plus 20 squared end root plus straight pi open parentheses 21 close parentheses squared
equals straight pi open square brackets 57 square root of 625 plus 441 close square brackets equals 22 over 7 cross times 1866
So, surface area of 10 buckets equals 22 over 7 cross times 1866 cross times 10 equals 58622.1 space cm squared
So, the cost of aluminium sheet equals 58622.1 cross times 42 over 100 equals Rs. space 24621
l=R-r2+h2

Answered by Renu Varma | 15th Mar, 2021, 02:47: PM