Answer:
108.
Step-by-step explanation:
"At this rate, ..." means we're to assume Nancy's score is proportional to the number of holes:
score/18 = 24/4
Multiplying by 18, we get ...
score = 18(24/4) = 18(6) = 108
Nancy can expect a score of 108 on 18 holes.
(if this isn't right, tell me and I will make sure to recheck my work :).
