Question

•the total amount paid for the initial deposit and 6 months of rent is the same at all three apartment complex, $5150

Answer 1

Initial dep for A = $200
for A, B, C :
initial dep  + 6 (monthly rent) = $5150

For A:
$200 + 6(monthly rent A) = $5150
monthly rent A = (5150 - 200) / 6 = $825
For B:
monthly rent B = monthly rent A - $25 =  $800 
initial dep  B  +  6(800) = 5150
initial dep B = 5150 - 4800 = $350
For C:
initial dep C = initial dep B + $150 = $500 
$500 + 6(monthly rent C) = 5150
monthly rent C = (5150 - 500) / 6 = $775