Angles Made by Clock

Practice questions:

Find the angle made by the hands of a clock when the time is....

8:45 6:00 9:37 . 2:20 . 4:15 . 3:25 . 4:30

1:45 . 3:40 . 1:00 . 2:30 . 5:15 . 10:30 . 11:20

When after 7:00 would the hands of the clock make a 90 degree angle?

Answers:

8:45 (7.5 degrees) 6:00 (180) 9:37 (66.5) 2:20 (50) 4:15 (37.5) 3:25 (47.5) 4:30 (45)

1:45 (142.5) 3:40 (130) 1:00 (30) 2:30 (105) 5:15 (67.5) 10:30 (135) 11:20(140)

A 90 degree angle would happen at 7: 21': 49"

The formula is

180 - | 180 - | m * 6 - (h * 30 + m * 0.5) |

Heres the complete formula.. for better understanding.. ABS is absolute value

180 - ABS (180 - ABS ( m * 6 - (h * 30 + m * 0.5) ) )

ABS((60(hour) - 11(minutes) /2)

MORE PRACTICE

Answers:

1 a. 45 degrees, b. 100 degrees, c. 142.5 degrees, d. 67.5 degrees, e. 162.5 degrees, f. 42.5 degrees

2 a. 123 degrees, b. 111 degrees, c. 42 degrees, d. 65.5 degrees

3 These are some possible answers: a. 3:00 or 9:00, b. 4:00 or 8:00, c. 2:30 or 9:30, d. 5:30 or 7:30 (need the hour and minute hand to be "half a step" apart since there are 30 degrees between each number on the face of the clock.)

Google Sites

Report abuse