Answer
$\pm 3.75$
Work Step by Step
The middle term of three consecutive terms of a geometric sequence can be found using the geometric mean formula:
geometric mean = $\sqrt {5 \bullet 2.8125}$
Multiply terms within the radicand first:
geometric mean = $\sqrt {14.0625}$
Take the square root:
geometric mean = $3.75$
The missing term could be either the geometric mean or its opposite, so we need to include both positive and negative values:
missing term = $\pm 3.75$
