The geometric mean of the observations *x _{1}, x_{2}, ……, x_{n} *is defined as

For simple frequency distribution,

For grouped frequency distribution, *x1 *is taken as class mark.

NOTE: 1. The logarithm of the G.M. of a variate is the A.M. of its logarithm.

- G.M. = 0 iff a single variate value is zero.
- G.M. is not used if any variate value is negative.

**Example 2.** *Find the G.M. of the following distribution*

**Solution. **Here N = No. of days = 15.