Cucumbers - math puzzle
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In the morning a green-grocer puts 200 kg cucumbers outside in front of his shop. These cucumbers consists for 99% out of water. Because it is a warm day some water will evaporate. As a result, at the end of the day the cucumbers consist for 98% out of water. How many kg's of these cucumbers are left at the end of the day? |
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Also having birthday today? - math puzzle
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Out of how many people should a group at least consist in order to have that the probability that two persons out of that group are having birthday on the same day, is larger than 1/2? |
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High voltage pylons - math puzzle
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A wire with a length of 60 meter is hanging between two high voltage pylons. The wire is connected to the pylons at a height of 50 meters. The middle part of the wire is 20 meters above ground level. How far are the high voltage pylons standing apart? |
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