What am I doing wrong? I have followed formula and still my answer is wrong

Brenda bought a swimming pooll obtaining an 8 % add on interest installment loan from the bank. The pool cost 2,400, and the bank requires 15% down and qual monthy payments for two years. How much is Brendas monthly payment.
2400(100%-15%)=85
2400 X 85%+2040
2040X,08%X2=3264
3264/24 months+136

a-85.00
b-86.36
c-98.60
d-116.00

Your work indicates some misunderstanding.

85%x2400=2040 amount to be financed.
1.08x2040x2=2366financed amount.

Now divide that by 24

What a ripoff by the Bank.