Which has greater accuracy, the 10 mL graduated cylinder or the 50 mL graduated cylinder

You can estimate one more digit past the smallest division on the measuring device. If you look at a 10mL graduated cylinder, for example, the smallest graduation is tenth of a milliliter (0.1mL). That means when you read the volume, you can estimate to the hundredths place (0.01mL).

The 10ml would be more accurate.