Actually, I really do love this question. I would say is the best question in QC area I came across. Why ?
Actually you do not need either to touch your pencil and do the counts.
It is pure logic and the solution is in the stem
An off-season discount of 10% is being offered at a store for any purchase with list price above $500. Ok. So we do know that ABOVE a $500 purchase we will have a discount in the order of 10% but no more than this. Even if you buy an item of one million of dollars the discount is still 10%
No other discounts are offered at the store. John purchased a computer from the store for $459.The underlined part is the solution to the problem, eventually: John bought an item for $459 so he will not receive the discount. The price he have paid is full. However, We do not know whether the $459 price that John paid for the computer was with the discount offer or without the discount offer.
Hope this helps
Regards
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