2003 AMC 8 Problems/Problem 20
Contents
Problem
What is the measure of the acute angle formed by the hands of the clock at 4:20 PM?
Solution 1
Imagine the clock as a circle. The minute hand will be at the 4 at 20 minutes past the hour. The central angle formed between and is degrees (since it is 1/12 of a full circle, 360). By , the hour hand would have moved way from 4 to 5 since is reducible to . One third of the way from 4 to 5 is one third of 30 degrees, which is 10 degrees past the 4. Recall that the minute hand is at the 4, so the angle between them is , and we are done.
Solution 2
You may also use the formula to yield a result in only ~10 seconds
-sub_math
See Also
2003 AMC 8 (Problems • Answer Key • Resources) | ||
Preceded by Problem 19 |
Followed by Problem 21 | |
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All AJHSME/AMC 8 Problems and Solutions |
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