Find the minimum length in cm and correct tonearest whole number of th

1.	Find the minimum length in cm and correct tonearest whole number of the thin metal sheetrequired to make a hollow and closed cylindricalbox of diameter 20 cm and height 35 cm.Given that the width of the metal sheet is 1 m.Also, find the cost of the sheet at the rate of56 per m.
Answer» Let length of metal sheet be l and breadth be bBreadth b = 1m = 100 Cm radius of cylindrical box r = 10 Cmand Height h = 35 Cm Thus area of of closed cylindrical box = 2pi r h + 2 pi r^2= 23.141035 + 23.14100= 2198 + 628 = 2826 Cm sq Thus Area of box = area of Sheet 2826 = l b l = 2826/100 l = 28.26 CmThus length of sheet is 28.26 Cm Cost of 1 msq of sheet = 56 RsCost of 10000Cm Sq = 56/10000 RsCost of 2826 Cmsq = 56 * 0.2826 Rs = 15.8256 RsThus total cost of sheet is 15.8256 Rs

Find the minimum length in cm and correct tonearest whole number of the thin metal sheetrequired to make a hollow and closed cylindricalbox of diameter 20 cm and height 35 cm.Given that the width of the metal sheet is 1 m.Also, find the cost of the sheet at the rate of56 per m.

Answer»

Let length of metal sheet be l and breadth be bBreadth b = 1m = 100 Cm

radius of cylindrical box r = 10 Cmand Height h = 35 Cm

Thus area of of closed cylindrical box = 2pi r h + 2 pi r^2= 2*3.14*10*35 + 2*3.14*100= 2198 + 628 = 2826 Cm sq Thus

Area of box = area of Sheet

2826 = l * b l = 2826/100 l = 28.26 CmThus length of sheet is 28.26 Cm

Cost of 1 msq of sheet = 56 RsCost of 10000Cm Sq = 56/10000 RsCost of 2826 Cmsq = 56 * 0.2826 Rs = 15.8256 RsThus total cost of sheet is 15.8256 Rs