Respuesta :

The general Formula for a decreasing Annuity is:
[tex]P = ( \frac{(1+i)^n -1}{i (1+i)^n}) R [/tex]
For this example we have:
P = 78,000
n = 7*4 = 28
i = 8%/4 = 2% = 0.02

After substituting you can find value for R, rent.