Question

At 4 o' clock, the hands of a clock make an obtuse and a reflex angle. Calculate the size, in degrees, of each of these angles.

Answer 1

Given:

At 4 o' clock, the hands of a clock make an obtuse and a reflex angle.

To find:

The size of each of the angles in degrees.

Solution:

The hands of the clock cover 360° to complete a full round, therefore, if the clock has 12 markings, then for each marking the clock will cover:

360°/ 12 = 30°

At 4 o' clock, the hands of the clock will cover:

30° * 4 = 120°

The remaining angle will be:

360° - 120° = 240°

Hence the obtuse angle in this case will be 120° and the reflex angle made by the hands of the clock will be 240°.

Thus the obtuse angle in degrees is 120° and the reflex angle in degrees is 240°.

Answer 2

Step-by-step explanation:

1 hour =360

60'=360

1'=6 degree

at 4 o clock the hand of the clock completes 30 minutes

30=30×6=180

obtuse angle = 180 degree

reflex angle = 360 - 180

= 180 degree