Percentage offers with a maximum discount: find where the saving stops growing
By Erik Nilsen · Kroni3 min read
A percentage offer can have a maximum discount expressed in money. The saving then grows only until that cap is reached, even if your child adds more to the basket. Calculate both the percentage amount and the maximum before using the offer in a budget.
Use the smaller of two discount amounts
In a hypothetical example, a code gives 10 per cent off all eligible products, but never more than 20 units. There is no delivery charge. Your child considers an optional purchase costing 250 units before discount. The conditions and arbitrary amounts are invented.
Ten per cent of 250 is 25 units. The cap is 20, so the actual discount here is 20. The final price is 250 − 20 = 230 units. An answer of 225 would use the entire percentage amount and overlook the cap.
Write two lines: “calculated percentage: 25” and “maximum: 20”. Circle the smaller one. That is the discount to subtract. For a basket costing 120, the percentage amount is 12, below the cap. The final price is then 120 − 12 = 108.
Find the threshold where the discount reaches its maximum: 20 units are 10 per cent of 200. At 200, your child gets 20 off. At 250, they still get 20. At 300, they also get 20 under this example's rule.
See what an extra item really costs
If the basket already costs 200 and your child adds an item costing 50, payment rises from 180 to 230. The extra item costs the whole 50 in that basket because the discount no longer grows. It does not produce another 5 units off.
A realistic snag is comparing this code with one that has no cap. An uncapped offer of 8 per cent discounts a 250-unit basket by exactly 20. At 300, its discount is 24, more than the first offer's maximum. Compare actual final prices for the same basket rather than percentages alone.
Check that both offers cover the same products and really work as calculated. Your family does not need to add anything to “use the cap”. An offer does not change how much money your child has available.
Ask your family: “Is the percentage amount above or below the cap, and how much discount does this basket receive?”
Carry the calculation into your family agreement
Kroni can keep track of your child's virtual balance. The app does not transfer money, so any actual purchase is paid for outside it. Agree on what you will record, then check the amount with your child afterwards. Do not deduct a possible cost as though the purchase had already happened. Read about allowance in Kroni.
