In this guide
Build the original totalFollow the rounded value into another calculationLabel the fields by purposeKeep other costs separateUse the right number for reconciliationA rounded average is a display choice. If it is later multiplied back by the full quantity, the result may differ from the original purchase total. That difference can look like a missing payment or a pricing error unless the record preserves the calculation’s purpose.
The example uses Dream’s published 60- and 120-credit package amounts and explains arithmetic, not an accounting valuation method.
Build the original total
One 60-credit package costs USD 95.40 and one 120-credit package costs USD 178.80. Together they represent 180 purchased credits at USD 274.20. Dividing 274.20 by 180 gives approximately USD 1.523333 per credit. The full total remains the actual combined package-cost input in this example.
Follow the rounded value into another calculation
If a summary displays USD 1.52 per credit and another sheet multiplies 1.52 by 180, it reconstructs USD 273.60. That is USD 0.60 less than the original combined total. The difference arises because information was removed by rounding the average before multiplication. It is not evidence that either published package multiplication was wrong.
Label the fields by purpose
Keep actual package total, calculated average and displayed rounded average as distinct concepts. A small operation may not need three visible columns, but the underlying record should preserve enough precision and source values to reproduce the result. Do not silently edit a receipt amount so a rounded summary appears to balance. The record should explain the difference rather than hide it.
Keep other costs separate
An exchange charge or payment fee is a different input from a rounding difference. Add actual amounts only when known and state whether the calculation includes them. Do not infer an unidentified fee because two numbers differ. A service-action cost also needs the confirmed consumption quantity, which the purchased-credit average does not supply.
Use the right number for reconciliation
When matching an order and payment, use the actual quoted total and currency. When showing a concise internal average, label the approximation and retain the calculation. This lets the team use readable summaries without losing transaction accuracy. A precise-looking per-credit number should remain traceable to the real purchase mix and its original totals.
When a colleague reports a small discrepancy, first ask which values were rounded and at what stage. Reproduce the calculation from the original totals before investigating an unexplained charge. This separates a display effect from an actual transaction question. Keep the unrounded calculation available privately without presenting an unnecessarily long decimal as a customer-facing price.
Questions about this guide
Should I add a USD 0.60 fee to make the example balance?
No. The difference is explained by rounding the displayed average. A fee is a separate factual claim and should be recorded only when actual evidence identifies it. Preserve the original package totals instead of inventing an expense.