Question

The external and internal diameters of a hollow hemispherical vessel are 16cm
and 12cm resp. The cost of painting per sq.cm. of surface is Rs. 2.5. Find cost of
painting​

Answer 1

Step-by-step explanation:

given,

internal diameter=12 cm

external diameter =16cm

radius of internal =12/2=6cm

radius of external=16/2=8cm

surface area(internal)=2πr²=2×22/7 ×6×6=2×22×6×6/7=227cm²

surface area (external)=2πR²=2×22/7 ×8×8

=2×22×8×8/7=403cm²

cost of painting = cost of internal+ cost of external+cost of the ring= 2(227)+2(403)+2(π(R²-r²)

=454+806+2(22/7(8²-6²)

=1260+44/7(64-36)

=1260+44/7(28)

=1260+44×4

=1260+176=1436 approx

because the answer come 1436 I take the next number. so it came. if u can use this process. if u want the exact value.

Answer 2

Answer:

thisbis your answer i hoe its help you