Use some thinking to answer the following question. Suppose you have three identical prisms with congruent equilateral triangles as the end-polygons. Suppose you attach them by the rectangular faces so they are perfectly aligned. There will be some large faces created by two or more co-planar faces of the individual prisms: count each such large face as one. Given that, how many faces does the resultant solid have\nOptions:\n(A)  4\n(B)  6\n(C)  9\n(D)  10\n(E)  5
User
To arrange them as described I did as follows on my scratch paper (see the file attached), where I counted 4 sides and bottom, hence 4+1 = 5. So the final answer is (E).
Assistant