You spend $800 on a credit card in January and pay only the $25 minimum. At 24% APR, roughly how much of that $25 payment actually reduces your principal balance?
AThe full $25, because payments always reduce principal first
BAbout $9, because roughly $16 goes toward interest (24% ÷ 12 × $800) before principal is touched
C$0, because credit cards charge all interest upfront at the billing date
DThe full $25, because interest only compounds annually, not monthly
Monthly interest = (24% / 12) × $800 = $16. Of the $25 minimum payment, $16 covers interest and only $9 reduces the principal. This illustrates why minimum payments extend payoff timelines dramatically — most of the payment is consumed by interest, leaving the principal nearly intact month after month.
Question 2 Multiple Choice
A credit card offers 2% cash back on all purchases. You spend $600 in a month but can only pay half the statement balance, carrying $300 at 24% APR for three months before paying it off. Did the rewards program benefit you?
AYes — you earned $12 cash back on $600 of spending, which is free money regardless of interest
BNo — the interest on the $300 carried balance (~$18 over three months) exceeds the $12 cash back reward
CYes — cash back is calculated on total spending, not on the carried balance, so you always come out ahead
DNo — rewards programs are only valuable for premium cards with annual fees
Cash back = 2% × $600 = $12. Interest = (24%/12) × $300 × 3 months ≈ $18. Net outcome: −$6. The rewards program actually cost you money. This is the core lesson: rewards are only genuine benefits when you pay in full, because any interest charge quickly exceeds what rewards return. The 'rewards' are funded by the interest paid by cardholders who carry balances.
Question 3 True / False
The grace period on a credit card means you pay no interest on purchases, even if you carried an unpaid balance from the previous billing cycle.
TTrue
FFalse
Answer: False
Most cards eliminate the grace period once you carry a balance. When you have an outstanding balance from a previous month, new purchases begin accruing interest immediately — there is no 30-day interest-free window. The grace period is only active when you start each billing cycle with a $0 balance (having paid the previous statement in full). This is why partial payments can cost more than they appear.
Question 4 True / False
A $500 balance on a card with a $5,000 limit hurts your credit score more than a $500 balance on a card with a $1,000 limit, even though the dollar amount owed is identical.
TTrue
FFalse
Answer: True
Credit utilization is measured as a ratio: balance ÷ credit limit. On the $5,000-limit card, utilization = 10%. On the $1,000-limit card, utilization = 50%. Credit scoring models treat higher utilization ratios as a sign of financial stress, regardless of the absolute dollar amount. Keeping utilization below 30% (and ideally below 10%) is more important than keeping the balance at a specific dollar level.
Question 5 Short Answer
Why do financial advisors say credit card rewards are only 'real' benefits if you pay your statement balance in full every month?
Think about your answer, then reveal below.
Model answer: Credit card APRs (typically 20–30%) are far higher than any rewards rate (typically 1–5%). Even a generous 2% cash back card returns $2 per $100 spent, while a 24% APR charges roughly $2 per month on a $100 carried balance. A single month of carrying a balance cancels the rewards on that spending. Rewards are funded by the interest paid by cardholders who carry balances — so those who pay in full effectively receive a subsidy from those who don't.
The math is unambiguous: interest costs scale with the balance and the time it's carried, while rewards are a fixed percentage of spending. As soon as interest begins accruing, it outpaces the reward rate within weeks. 'Earning rewards' while carrying a balance is a net loss, not a benefit.