"I am unsure how to answer this question:

Researchers at the University of Pennsylvania School of Medicine have determined that children under 2 years old who sleep with the lights on have a 31% chance of becoming myopic before they are 16. Children who sleep in darkness have a 26% probability of becoming myopic. A survey indicates that 27% of children under 2 sleep with some light on. Find the probability that a random child under 2 will become myopic before reaching 16 years old."