In a clever and cost-effective solution, one can use Euro coins as standard weights for measuring objects up to 100 grams with an accuracy of about 0.5 grams. By combining different coins, such as the 0.01, 0.02, 0.05, 0.10, 0.20, and 0.50 Euro coins, various round weights can be achieved. Combinations like 15 grams and 20 grams are essential for measuring to a resolution of 5 grams. Adding the 17.5 gram weight improves the resolution to 2.5 grams. While the 25 gram weight is not necessary, it is convenient. The smaller coins provide more weight for a lower cost, making them ideal for constructing a set of standard weights.
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