Based on the information provided, Lena, Sheldon, Naomi, Mark, and Paula each made predictions about the weight of the diamond ring that Lena found in the parking lot. Lena said it weighed 0.275 carats, Sheldon thought it was closer to 0.58 carats, Naomi predicted 0.625 carats, Mark disagreed and said 0.8 carats, and Paula went with 0.875 carats.
To determine who had the correct measurement, we need to compare their predictions to the actual weight of the diamond ring, which is given as 5/8 carats.
Converting 5/8 carats to a decimal, we get 0.625 carats.
Therefore, **Naomi** had the correct measurement with her prediction of 0.625 carats, which matches the actual weight of the diamond ring.
