Answer: the maximum number of visits would be 38
Explanation:
A person can pay $7 for a membership to the history museum and then go to the museum for just $1 per visit.
Let x represent the number of visits that the person makes to the museum after paying for the membership. This means that if the person makes x visits to the history museum, the total cost would be
7 + x
If a member of the history museum pays a total of $45. It means that the number of visits that he can make to the history museum would be
7 + x = 45
x = 45 - 7 = 38