A hollow hemispherical bowl is made of silver with its outer radius 8 cm and inner radius 4 cm respectively. The bowl is melted to form a solid right circular cone of radius 8 cm. The height of the cone formed is
A person lent certain sum of money at 5% per annum simple interest and in 15 years the interest amounted to Rs 250 less than the sum lent. What was thesum lent (in Rs)?