If the base radius and the height of a right circular cone are increased by 20%, then the percentage increase in volume is approximately. (a)   60     (b)  68        (c)  73        (d)  78

Explanation

To find the percentage increase in the volume of a right circular cone when the base radius and height are increased by 20%, we can follow these steps:

### Step 1: Understand the formula for the volume of a cone
The volume \( V \) of a right circular cone is given by the formula:
\[ V = \frac{1}{3} \pi r^2 h \]
where \( r \) is the base radius and \( h \) is the height of the cone.
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