Fruit Seller’s Paradox

admin — Wed, 03 Mar 2010 04:16:44 +0000

Fruit Seller's Paradox- Each of two apple women had 30 apples for sale. The first sold hers at the rate of 2 for a nickel, the second at the rate of 3 for a nickel. At the end of the day their respective receipts were 75 cents and 50 cents, or $1.25 in all.

The next day the women decided to do business together, so they pooled their 60 apples and sold them at the rate of 5 for a dime (2 for a nickel plus 3 for a nickel). Upon counting their joint receipts at the end of the day they were dismayed to find that they had only $1.20. They searched all about them for that other nickel, and wound up by bitterly accusing each other of having taken it. Where was it? (1 Nickel = 5 Cents)

Windy Flight Paradox

admin — Sun, 21 Feb 2010 17:22:15 +0000

A plane makes a trip from New York to Washington and back to New York. Call the distance between the two cities 200 miles and the speed of the plane 100 miles per hour. Then the time required for the round trip, ignoring stops, is 4 hours. Now suppose there is a strong wind which blows throughout the entire trip with the same speed and in the same direction-from New York directly toward Washington, say. Then the tail wind on the way south will speed up the plane to the same extent that the head wind will retard it on the way north.

Windy Flight Paradox

In other words, both the average speed of the plane and the time for the round trip will be independent of the speed of the wind. But this means that the plane can still make the trip in 4 hours even though the speed of the wind is greater than that of the plane, in which case the plane would be blown backward on the trip from Washington to New York!

Quicker Maths » paradox

Fruit Seller’s Paradox

Windy Flight Paradox