SSC CGL 30 Aug 2015 Paper

At 7 : 20,
Number of hours
= 7 $\frac{20}{60}$ = 7 $\frac{1}{3}$ hours
= $\frac{22}{3}$ hours
The hour–hand traces 360° in 12 hours.
∴ Angle traced by hour hand in $\frac{22}{3}$ hours
= $\frac{360°}{12}\times \frac{22}{3}$ = 220°
Since Minute hand traces 360° in 60 minutes.
∴ Angle traced by minute hand in 20 minutes = $\frac{360°}{60}$ × 20
= 120°
∴ Required angle
= 220° – 120° = 100°