Answer
$P(at~least~7)=P(x\geq7)=0.550$
On about 550 of every 1000 days, there will be at least 7 hits to a Web site between 7:30 p.m. and 7:35 p.m.
Work Step by Step
The probability that there will be at least 7 hits to a Web site between 7:30 p.m. and 7:35 p.m. is the complement of the probability that there will be fewer than 7 hits to a Web site between 7:30 p.m. and 7:35 p.m.
Using the Complement Rule (see page 275):
$P(at~least~7)=P(x\geq7)=1-P(x\lt7)=1-0.450=0.550$
