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To solve the problem, you need to find the height \( h \) of the middle post of a railing, given the heights of the outer posts \( h_1 = 2.6 \) meters and \( h_2 = 1.4 \) meters. The middle post is evenly spaced between the two outer posts. This setup suggests a linear decrease in height from \( h_1 \) to \( h_2 \) because the middle post is exactly halfway between them. To find \( h \), calculate the average of \( h_1 \) and \( h_2 \): \[ h = \frac{h_1 + h_2}{2} = \frac{2.6 + 1.4}{2} = \frac{4.0}{2} = 2.0 \text{ meters} \] So, the height of the middle post is 2.0 meters.