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Question
The number of parallelograms that can be formed from a set of four parallel lines intersecting another set of three parallel lines is ______.
Options
6
18
12
9
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Solution
The number of parallelograms that can be formed from a set of four parallel lines intersecting another set of three parallel lines is 18.
Explanation:
We know that to form a parallelogram, we require a pair of lines from a set of 4 lines and another pair of lines from another set of 3 lines
∴ Required numbers of parallelograms = 4C2 × 3C2
= 6 × 3
= 18
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