Answer
$P(\text{physical science or life science})=0.087+0.203=0.290$
If we select 1000 doctoral degrees from U.S. universities in 2009, we would expect about 290 to be physical science or life science.
Work Step by Step
$P(\text{physical science or life science})=P\text{(physical science}) + P(\text{life science})=0.087+0.203=0.290$.
This is the Addition Rule for Disjoint Events.
