from typing import Dict


def linear_utility(exchange_params_by_currency: Dict[str, float], balance_by_currency: Dict[str, int]) -> float:
    """
    Compute agent's utility given her utility function params and a good bundle.

    :param exchange_params_by_currency: exchange params by currency
    :param balance_by_currency: balance by currency
    :return: utility value
    """
    money_utility = [exchange_params_by_currency[currency] * balance for currency, balance in balance_by_currency.items()]
    return sum(money_utility)