NCERT Exemplar Solutions
Class 6 - Mathematics - Unit 2: Geometry - Multiple Choice QuestionsQuestion 3
Class 6 - Mathematics - Unit 2: Geometry - Multiple Choice Questions
Question. 3
Number of line segments in Fig. 2.5 is
(A)
5
(B)
10
(C)
15
(D)
20
Detailed Answer with Explanation:
Step 1: Count the points on the line in the figure. There are 5 points.
Step 2: One line segment is formed by choosing any two points.
Step 3: So we must count the number of pairs of points from 5 points.
Step 4: Use combinations:
\(\text{Number of pairs} = {}^5C_2\)
\({}^5C_2 = \dfrac{5\times 4}{2\times 1}\)
\(= \dfrac{20}{2}\)
\(= 10\)
Answer: 10 (Option B).