Percentage of the starting amount or the remainder: one purchase can be 30 and 75 per cent
By Erik Nilsen · Kroni3 min read
A percentage always needs an amount it is calculated from. After your child spends some money, a new purchase can be a small share of the original amount and a large share of what remains. Both descriptions may be correct, but answer different questions.
Write the amount beneath the percentage
In a hypothetical example, your child started with 100 units actually received and spent 60 on optional purchases. Another 100 − 60 = 40 remain. They now want an item costing 30. The figures and purchases are arbitrary teaching examples.
The item costing 30 is 30 / 100 = 30 per cent of the original amount. It is also 30 / 40 = 75 per cent of the money still available. After buying, 40 − 30 = 10 remain.
Of the starting amount, 60 + 30 = 90 have then been spent, or 90 per cent. The final 10 are 10 per cent of the starting amount but 25 per cent of the 40 available just before the new purchase. The same remainder of 10 is being compared with two different bases.
Draw ten boxes for the original 100. Six are already spent and four remain. The new purchase uses three of the four remaining boxes. Your child can see three out of ten and three out of four without treating them as contradictory.
Use the description answering today's decision
A realistic snag is your child saying “it is only 30 per cent” and an adult answering “no, it is 75”. First ask “of which amount?”. Neither calculation has to be wrong. When considering what remains today, 40 is the relevant available amount.
If your family agreed to retain at least 15 for another personal wish, this purchase fails the plan by leaving only 10. Calculate an item costing 25, which would leave 15, or let the purchase wait.
This is not a rule saying children should spend only a particular percentage. It describes a concrete decision before money is spent. Use actual available money rather than an expected future payment when asking what your child can pay now.
Ask your family: “Which amount are we calculating the percentage from, and how much money will remain after the purchase?”
Clarify what the virtual balance represents
Kroni keeps track using a virtual balance and does not transfer money. Cash your child has received and amounts an adult still owes are different things. This exercise concerns money actually received. Agree how it fits your record so the same amount is not counted both as received and still unpaid. Read about allowance in Kroni.
