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When interest starts earning interest

At a constant rate, compound interest repeatedly adds interest to the amount earning the next round. That follows a different path from adding the same amount each period; a hypothetical path is not a forecast.

3–7 min

Questions you could explore

  • When does the original principal stop being the whole calculation base?
  • Which assumptions would need changing to describe a real account?

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Why can the official inflation rate differ from your shopping bill?

A national price index combines thousands of goods and services that no single household buys in the exact same proportions. Because the Consumer Price Index uses average spending weights, a jump in rent or groceries can hit your personal budget much harder than the headline inflation figure suggests.

4–5 min
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An hour can be free of charges and still be scarce. Choosing one use means giving up the best available alternative, which is the opportunity cost even when no money changes hands.

3–5 min
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An uncertain large loss for one person can become part of a wider pool of risks. Insurance connects that pooling with a contract and a premium, while the contract still determines which losses are covered.

3–7 min
When interest starts earning interest | Speech Topic | speaking.app