Illuminations: Clock Hands II

Clock Hands II

A pocket watch is placed next to a digital clock. Several times a day, the product of the hours and minutes on the digital clock is equal to the number of degrees between the hands of the watch. (The watch does not have a second hand.) As you can see, 10:27 is not one of those times — the angle between the hands is not 270°. If fractional minutes aren’t allowed, find the times at which the product of the hours and minutes is equal to the number of degrees between the hands.

This brainteaser was written by Derrick Niederman.

STEAM Topics Resource Audience Grade Level Tags PDFs

Math Topics

Algebra & Pre-Algebra, Geometry

High School

9th Grade, 10th Grade, 11th Grade, 12th Grade

Math Puzzles, Time

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Illuminations (National Council of Teachers of Mathematics)

National Council of Teachers of Mathematics

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