Answer: The average percentage change per year was 0.3652%.
Step-by-step explanation:
Given: In 1992, 18.6% of the world population was undernourished.
In 2015, 10.9% of the population was undernourished.
The average percentage change per year will be
[tex]\dfrac{\text{Percentage in 2015- Percentage in 1992}}{201-1992}\\\\=\dfrac{18.6\%-10.9\%}{2015-1992}\\\\=\dfrac{8.4\%}{23}\approx0.3652\%[/tex]
Hence, the average percentage change per year was 0.3652%.