In the given figure, ∠ONY = 50° and ∠OMY = 15°.

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In the given figure, ∠ONY = 50° and ∠OMY = 15°. Then the value of the ∠MON is

1. 30°
2. 40°
3. 20°
4. 70°

Correct Option: D

According to question ,

In ∆ ONY, ON = OY = radii
∠ONY = 50° = ∠OYN
∴ ∠NOY = 180° – 2 × 50° = 80°
In ∆ OMY,
OM = OY = radii
∴ ∠OMY = ∠OYN = 15°
∴ ∠MOY = 180° – 2 × 15° = 150°
∴ ∠MON = 150° – 80° = 70°