This is the 671st most frequent Korean word.
증가
Increase.
In this sentence, '증가' (increase) is used as a noun converted into a verb form through the combination with '하고 있다', showing an ongoing increasing action of the population.
인구가 빠르게 증가하고 있습니다.
The population is rapidly increasing.
Here, '증가하는' is formed as a verb-like adjective modifying '비용', describing costs that are increasing.
증가하는 비용이 가계에 부담을 주고 있습니다.
Increasing costs are burdening households.
In this context, '증가' is a noun referring to the increase accompanying technological advancement.