Question

It costs Rs. 2200 to paint the curved surface of a solid cylindrical pillar of
height 10m. If the cost of painting is at the rate of Rs.20 per m2, find (i) its
curved surface area (ii) radius of the base (iii) volume of the material
used to make it (iv)find the mass of the material in it, if 1m' of the
material has a mass of 78kg​

Answer 1

Answer:

Total cost of point=2200Rs.

cost of point/m

2

=20Rs.

depth of vessel=10m

Inner curved surface area painted=

cost/m

2

totalcost

=

20

2200

=110m

2

Now, 2πrh=110m

2

2×

7

22

×r×10=110

r=

2×22×10

110×7

=1.75m

∴ radius of the base is 1.75m.

capacity of vessel=πr

2

h=

7

22

×1.75×1.75×10

=96.25m

3