Subscription fee for a month = $ 5
Subscription fee for a writer who signs up = $ 5
Number of subscribers last month = 200
New members who joined the website = 40
Number of subscribers who left the website = 10
Hence, total subscribers in the present time = 
Now, total subscription fee received this month = 
Hence, the answer is $1150.
Given:
adults = x
male = 7x + 1
female = (7x + 1)/2
total number of people = 82
x + (7x + 1) + [(7x +1)/2] = 82
2x/2 + (14x + 2)/2 + (7x + 1)/2 = 82
2x + 14x + 2 + 7x + 1 = 82 * 2
23x + 3 = 164
23x = 164 - 3
23x = 161
x = 161/23
x = 7
adults = x = 7
males = 7x + 1 = 7(7) + 1 = 49 + 1 = 50
females = (7x+1)/2 = 50/2 = 25
7 + 50 + 25 = 82
Answer: 1 is not a perfect square. 3 is the only prime number one less than a square.
