@MrsRobinson 973545 wrote:
Smartarse.
my first thought was 30.
but it’s 30 x 2 = 60. right?
according to the Australian news (and what I worked out myself) it is 60 degrees.
I admit to using a modern Japanese pocket calculator (the same model that would be allowed in a UK high school exam at this level) to check my answer and taking advantage of the clue that the professors who write these exam paper usually drop into the question; as well as half-remembered stuff from 1980s when I was sharper at maths and computer programming (the solution is related to methods used to plot a circle on a bitmapped display)
They tell you exactly how many sides the coin has – it is a polygon approximating to a circle (360 degrees). Dividing that by 12 gives 30.
If the two coins are stacked next to each other and the sides are perpendicular the angle Θ will be twice that of the angles between each coin and the vertical plane. 30 * 2 = 60 😉 There is an extra 30 degree angle in the horizontal plane due to an adjacent side of the polygon which makes Θ look bigger than it actually is (but could also be a clue to a more observant youngster if their maths teachers were any good).
