Practice!

Sample Problem

The hour hand of a clock is 2.5 in long. Find the distance travelled by the tip of the hour hand in 6 hours. Round your answer to two decimal places. (Use π = 3.14)

The distance travelled by the tip of the hour hand in 6 hours is inches.

Solution

Circumference of the circle that the hour hand makes:

3.14 × 2.5 in × 2 = 15.7 in

The hour hand turns half round in 6 hours.

∴The distance travelled by the tip:

15.7 in ÷ 2 = 7.85 in

The distance travelled by the tip of the hour hand in 6 hours is 7.85 inches.