10 grade maths> A blacksmith has a rectangular sheet of I...

A blacksmith has a rectangular sheet of Iron. He has to make a cylindrical vessel both circular ends are closed. When he minimizes the wastage of the sheet of iron, then what is the ratio of the wastage to the utilised area of sheet?

Ayush , 10 Years ago

Grade 11

3 Answers

Sourabh Singh

zThe length of the square sheet will be equal to 4r + h .
From this information you can relate both the values in a common variable and you will get the ratio.

Last Activity: 10 Years ago

Ayush

why the length will be 4r+h.............................................................................................................?

Last Activity: 10 Years ago

Akhil

Let length l
Breadth b hence radius
r=b/4
h=b=4r
2πr=l-2r
58r/7=l
lb=232r²/7
2πrh+2πr²=176r²/7 + 44+r²/7=220r²/7
Difference=12r²/7
Ratio=12/220=3/55

Last Activity: 7 Years ago