A not-so-well-known puzzle is called a Curry Triangle, but it is even more myste-rious tha...

A not-so-well-known puzzle is called a Curry Triangle, but it is even more myste-rious than the one in Problem 1. However, it contains the same type of fallacy. (See if you can find it.) Start with an isosceles triangle having a base of 10 units and height 12. Hence, its area is • 10 • 12 = 60 square units. When the six pieces in the dissection of the triangle are rearranged face up as shown in (a), the result is an apparent loss of two square units. However, in (b), some of the pieces are turned face down, and the resulting loss of area is only one square unit!