A sedimentary rock made up of fragments with rounded edges is called a conglomerate.

Here's why:

* Rounded edges: This indicates the fragments have been transported a significant distance, as the edges get worn down during transport.

* Fragments: Conglomerates are made up of larger pieces of rock (gravel size or larger).

* Sedimentary: This means the rock was formed from the accumulation and cementation of sediments.

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