Final answer:
When a firm decreases its debt while maintaining its current equity and net income, the debt-to-equity ratio will decrease.
Step-by-step explanation:
When a firm decreases its debt while maintaining its current equity and net income, the debt-to-equity ratio will decrease. In this case, the firm currently has $600 in debt for every $1,000 in equity, which means the debt-to-equity ratio is 0.6. If the firm uses some of its cash to decrease its debt, let's say the debt becomes $500, while the equity remains at $1,000. The new debt-to-equity ratio would be 0.5, indicating a decrease in the ratio.