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Clock Hands

This investigation explores using different shapes as the hands of the clock. What things occur as the the hands move.

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Watch the Clock

During the third hour after midnight the hands on a clock point in the same direction (so one hand is over the top of the other). At what time, to the nearest second, does this happen?

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Estimating Angles

How good are you at estimating angles?

Take the Right Angle

Age 7 to 11 Challenge Level:

Abby, Antony, James and Peter from Gateway school in Carterton wrote to say:

We found 22 right angles in 12 hours. All the right angles are listed below:
12:16 12:49 1:22 1:54 2:27 3:00 3:33 4:05 4:39 5:11 5:44 6:16 6:49 7:22 7:54 8:27 9:00 9:33 10:05 10:39 11:11 11:44.

One of these is a minute out according to the NRICH clock. Can you find which one?

William and Alex at Maadi British International School, Cairo used a wrist watch to work out the problem and agreed there were 22 right angles, so did Eliza and Milli from St Hilda's School.