How many parallelograms are there in the following figure?
Step-by-step Solution:
Answer: (D) 30
To find the total number of parallelograms in the figure, use a systematic counting method based on the grid of horizontal and slanted lines.
There are 3 horizontal lines and 5 slanted lines. A parallelogram is formed by choosing any two horizontal lines and any two slanted lines.
Number of ways to choose 2 horizontal lines from 3: C(3,2) = 3
Number of ways to choose 2 slanted lines from 5: C(5,2) = 10
Total number of parallelograms = 3 × 10 = 30