The rule for a pattern is “circle, square, circle, triangle, circle, rectangle”. What is the eighteenth word in the pattern?
Based on the given pattern, we can identify the following sequence:
Circle, Square, Circle, Triangle, Circle, Rectangle, Circle, Square, Circle, Triangle, Circle, Rectangle, Circle, Square, Circle, Triangle, Circle, Rectangle...
From this sequence, we can observe that the pattern repeats every 6 words. Therefore, to find the 18th word, we need to identify the position of the 18th word within the sequence of 6.
18 divided by 6 gives us a quotient of 3 with a remainder of 0. This implies that the 18th word falls into the third repetition of the pattern.
Within the third repetition, the 18th word corresponds to the second word, which is a "square".
Therefore, the eighteenth word in the pattern is "square".