Puzzles to test mathematical skills. Set by Anita Straker.
From midnight one night to midnight the next, exactly how many times do the hands of a clock form a right angle?
How many times do they form a straight line?
* Leap years
Age 11-13 2002 is not a leap year.
A leap year is a calendar year of 366 days - February 29 being the additional day that occurs every four years - those whose number is divisible by four, like 1996.
But years at the turn of the century are leap years only if they are multiples of 400.
So 2000 was a leap year, but 2100 will not be.
How many leap years will there be from 2003 to 3003?
Solutions from page 39
44 times at right angles. Usually, in each two hour period the hands are at right angles four times. But between 2 o'clock and 4 o'clock, and between 8 o'clock and 10 o'clock, they are at right angles only three times.
They are in a straight line 22 times.