Answer
Yes, this result is surprising.
Work Step by Step
$P(trusts~organized~religion)=0.18$
The events "American 1 trusts organized religion", "American 2 trusts organized religion" and "American 3 trusts organized religion" are independent.
Now, using the Multiplication Rule (see page 282):
$P(all~3~trust~organized~religion)=P(American~1~trusts~organized~religion)\times P(American~2~trusts~organized~religion)\times P(American~3~trusts~organized~religion)=0.18\times0.18\times0.18=0.005832$
$P(all~3~trust~organized~religion)\lt0.05$. It is an unusual event, so, we can conclude that this result is surprising.
