Given total cost =Rs.176
Rate of charge = 25 paise per sq.cm
The total cost of painting cone = Total surface area of cone × Rate of charge
⇒ Total surface area of cone = TotalcostofpaintingconeRateofcharge
= 1760.25=704cm2
Let the radius of cone be rcm
slant height (l)=25cm
Total surface area of cone =πr(l+r)=704
⇒227×r(r+25)=704
⇒r2+25r=704×722
⇒r2+25r=224
⇒r2+32r−7r−224=0
⇒r(r+32)−7(r+32)=0
⇒(r+32)(r−7)=0
Then r=7 and r=−32
Discarding negative value as radius cannot be negative
Therefore, radius of cone=7cm
By Pythagoras Theorem,
height of cone = √l2−r2
=√(25)2−(7)2
=√625−79
=√576=24 cm
Therefore, volume of cone = 13πr2h
=13×227×(7)2×24
=22×7×8
=1232cm3