def get_expected_value_r(sum_fo_r, sum_fo, fg):
	"""
	Get the expected frequency from the given parameters.

	Parameters
	----------
	> `sum_fo_r`: sum of frequencies for a particular observed response (row sum)
	> `sum_fo`: sum of all observed frequencies
	> `fg`: frequency of an observed group / category

	Returns
	-------
	The expected frquency value from the given parameters.
	"""

	return (sum_fo_r / sum_fo) * fg