NCERT Exemplar Solutions
Class 6 - Mathematics - Unit 2: Geometry - Fill in the Blanks

Question 24

Step 1: Recall the types of angles.

• Acute: \(\theta < 90^\circ\)
• Obtuse: \(90^\circ < \theta < 180^\circ\)
• Straight: \(\theta = 180^\circ\)

Step 2: Find angles at vertex O.

Each is formed by two rays starting from O.

• \(\angle AOB\)
• \(\angle BOC\)
• \(\angle COD\)
• \(\angle DOA\)

These are inside the figure and each has \(\theta < 180^\circ\).

Step 3: Find angles at vertices A, B, C, D that use point O.

Each is an interior corner angle of the shape.

• \(\angle OAB\)
• \(\angle OBC\)
• \(\angle OCD\)
• \(\angle ODA\)

Each of these also satisfies \(\theta < 180^\circ\).

Step 4: Count them.

There are 4 angles at O and 4 interior corner angles.

Total \(= 4 + 4 = 8\).

Step 5: Write the names.

\(\angle AOB,\; \angle BOC,\; \angle COD,\; \angle DOA,\; \angle OAB,\; \angle OBC,\; \angle OCD,\; \angle ODA.\)