Student: The sticks of same length are used to form a triangle as shown below.If 87 such sticks are used then how many triangles can be formed?
Options:
(A) 43
(B) 44
(C) 45
(D) 465
(E) 47.
Another student: Let's say, hmmm...
First triangle is formed by using 3 sticks, but any subsequent triangle may be formed by using 2 sticks. Therefore, If 1st triangles uses 3 sticks, Remaining sticks = 87 - 3 = 84. With these 84, we can form 42 triangles. So total = 42 + 1 = 43 Final answer: (A).