median
don steward
mathematics teaching 10 ~ 16

Wednesday, 18 October 2017

Monday, 16 October 2017

algebra problems


equation of a circle

an introduction to the equation of a circle
which can later be generalised, using pythagoras





Saturday, 26 August 2017

rounding to different amounts

usually rounding to a finer amount (5p or 5c) will provide a more accurate estimate to the true cost than rounding to e.g. the nearest 10p or 10c
but not always...





for three addends:
rounding to the nearest 5p is more accurate in 123 cases
rounding to the nearest 10p is more accurate in 28 cases
and for the remaining 69 cases, both methods of rounding are equally accurate

for four addends:
nearest 5p = 417 cases
nearest 10p = 105 cases
equally accurate = 193 cases

for five addends:
nearest 5p = 1210 cases
nearest 10p = 321 cases
equally accurate = 471 cases

[thanks to the National Mathematics Project team (published in the UK in 1989, Eon Harper et al) for these solutions and the suggestion for this task]

Tuesday, 22 August 2017

multiplication of big numbers

no calculators
coping with the noughts










Thursday, 17 August 2017

quadrilaterals on a 6 by 6 dotty grid



quadrilaterals on a 3 by 3 dotty grid

almost an antique
part of the South Nottinghamshire Project ('Journey into Maths')
by Alan Bell, David Rooke and Alan Wigley
published by Blackie in 1978
the teacher's guide (1) claims there are a total of 94 different positions
counting translations, reflections or rotations

an intention might be that students don't count transformations of each shape (initially anyway)




quadrilaterals on a 5 by 5 dotty grid