1/10 of the current U.S. population has diabetes. 25 of the people with diabetes have not been diagnosed with the disease. What fraction of the U.S. population has undiagnosed diabetes? Write the answer in simplest form.(1 point)

The fraction of the U.S. population that has undiagnosed diabetes is $\frac{25}{10\cdot10} = \boxed{\frac{1}{40}}$.