Answer
$P(at~least~one)=0.733$
In about 733 of next thousand 100 million vehicle miles, there will be at least one fatal accident.
Work Step by Step
The probability that there will be at least one fatal accident during the next 100 million vehicle miles is the complement of the probability that there will be no fatal accidents during the next 100 million vehicle miles.
Using the Complement Rule (see page 275):
$P(at~least~one)=P(x\geq1)=1-P(0)=1-0.267=0.733$
