110% of the Litecoin's value of the amount of bitcoin you want to borrow would be the best. (Or a coin with a stable value)
I don't quite understand what you are saying,
but I only need to borrow BTC and I will return it at least 130%-200$ after 10 days
Collateral - something pledged as security for repayment of a loan, to be forfeited in the event of a default.
as you say earlier:
110% of the Litecoin's value of the amount of bitcoin you want to borrow would be the best.
But I prefer, for example: I borrow 0.02 BTC and I return 0.04 BTC after 10 Days
And what will happen when you don't return here after 10 days without a collateral?