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A cone is cut through a plane parallel to its base and then the cone that is formed on one side of that plane is removed. The new part that is left over on the other side of the plane is called
a. a frustum of a cone
b. cone
c. cylinder
d. sphere

Solution:

From the question

A cone is cut through a plane parallel to its base and then the cone that is formed on one side of that plane is removed. The new part that is left over on the other side of the plane is called a. a frustum of a cone, b. cone, c. cylinder, d. sphere

Therefore, the new part that is left over on the other side of the plane is called a frustum of a cone.

✦ Try This: A vessel is in the form of a frustum of a cone. The area of the ends of the frustum cone are 122 cm² and 205 cm². If the curved surface area is 305 cm². Find the total surface area.

The formula to find the total surface area is

TSA = π (R + r)s + πR² + πr²

It is given that

π (R + r)s = 305 cm²

πR² = 122 cm²

πr² = 205 cm²

Substituting the values

TSA = 305 + 122 + 205

TSA = 632 cm²

Therefore, the total surface area is 632 cm².

☛ Also Check: NCERT Solutions for Class 10 Maths Chapter 13

NCERT Exemplar Class 10 Maths Exercise 12.1 Problem 7