Q. 53.7( 13 Votes )

# A container, open

Answer :

Given: height of container frustum = h = 16 cm

Diameter of lower circular end = 16 cm

Diameter of upper circular end = 14 cm

Radius of lower circular end = r = 16/2 = 8 cm

Radius of upper circular end = R = 14/2 = 7 cm

Cost of 100 cm2 metal sheet = 10 Rs

Cost of 1 cm2 metal sheet = 10/100 = 0.1 Rs

Formula: Total surface area of frustum = πr2 + πR2 + π(R + r)l cm2

Where l = slant height  l = 16.0312 cm

Since the top is open we need to subtract the area of top/upper circle from total surface area of frustum because we don’t require a metal plate for top.

Radius of top/upper circle = R

Area of upper circle = πR2

area of metal sheet used = (total surface area of frustum)-πR2

= πr2 + πR2 + π(R + r)l- πR2 cm2

= πr2 + π(R + r)l cm2

= π × (82 + (7 + 8)16.0312) cm2

= 3.14 × 304.468 cm2

= 956.029 cm2

956.029 cm2 metal sheet is required to make the container.

Cost of 956.029 cm2 metal sheet = 956.029 × cost of 1 cm2 metal sheet

= 956.029 × 0.1 Rs

= 95.6029 Rs

Cost of metal sheet required to make container = 95.6029 Rs

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos  Trigo Marathon Part 245 mins  Trigo Marathon Part 146 mins  Application of Trigo Important Questions44 mins  Arithmetic Progression and 'nth' Term of AP55 mins  Chemical Properties of Metal and Non Metal61 mins  Extraction of Metal56 mins  Purification of Metals60 mins  Properties of Metal and Non Metal59 mins  Introduction of Metal and Non Metal59 mins  Heights and Distances - II45 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation view all courses 