Exams › SSC CGL (Prelims) › General

How many diagonals does a pentagon have?

1. 5
2. 7
3. 10
4. 15

Correct answer: 5

Solution

The number of diagonals in an n-sided polygon is n(n-3)/2. For a pentagon, n = 5, so the number of diagonals is 5(5-3)/2 = 5.

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