Ribosomes and mitochondria are found in specific locations within cells, serving distinct but related functions:

Ribosomes

• Ribosomes are small organelles responsible for protein synthesis. They are made of ribosomal RNA and proteins.
• In eukaryotic cells, ribosomes can be found:
  • Free-floating in the cytoplasm.
  • Attached to the rough endoplasmic reticulum (ER).
  • Bound to the nuclear envelope.
• Ribosomes are also present in prokaryotic cells and in organelles of bacterial origin such as mitochondria and chloroplasts.
• Mitochondria contain their own specialized ribosomes called mitoribosomes, which synthesize proteins encoded by mitochondrial DNA essential for mitochondrial function

Mitochondria

• Mitochondria are membrane-bound organelles found in the cytoplasm of eukaryotic cells.
• They are the site of cellular respiration and ATP production.
• Mitochondria have their own DNA and ribosomes (mitoribosomes), reflecting their bacterial ancestry.
• Mitoribosomes are attached to the inner mitochondrial membrane and translate mitochondrial mRNAs.
• Most mitochondrial proteins, however, are synthesized by cytoplasmic ribosomes and imported into mitochondria

Summary:

• Ribosomes are found free in the cytoplasm, attached to the ER, and inside mitochondria and chloroplasts.
• Mitochondria are located in the cytoplasm of eukaryotic cells and contain their own ribosomes (mitoribosomes) attached to the inner mitochondrial membrane.

Thus, you can find ribosomes both in the cytoplasm (free or on ER) and inside mitochondria, while mitochondria themselves reside in the cytoplasm of eukaryotic cells