Re: That'll Teach 'Em - Long Division

MikeH wrote in
1145436440.550284.322840@xxxxxxxxxxxxxxxxxxxxxxxxxxxx:

And these were - I think - kids who were expected to do well in their
GCSEs.

I can accept - just - that some of the techniques I learned in the 60s
are probably redundant today, such as all the messing about with
number bases to divide Imperial units, but something as basic as long
division ought to be taught in primary schools.

The thought of going through the tedious process of dividing a weight of 3
tons 5 cwt 13 lb 7 oz into 11 equal shares makes me shudder! I'd be inclined
to convert the whole lot into ounces, divide that huge number by 11 and then
convert the result back into tons, cwt, lb and oz.

Likewise with log tables and slide rules: familliarity the use of log
tables, mantissas and the bar notation is probably not necessary these days
when a calculator is so much quicker and easier. You should have an
understanding of what logs are and the fact that adding or subtracting them
is equivalent to multiplying or dividing the original numbers.

However I agree that simple long multiplication and division should still be
taught, if only so you are not totally stumped if your calculator fails. The
ability to estimate the rough magnitude of the answer is also something that
seems to have been lost with the introduction of the calculator: if you are
multiplying 123 by 456, you expect an answer of very roughly 10^4, so if
your calculator gives you answers of 0.0000000023424 or
439852989852983592865925 you've pressed the wrong buttons.

I remember a teacher when I was at school in the 1970s whose standard
punishment for any misdemeanour was "cubes". He'd go round the class getting
boys to call out digits (the number of digits depended on the severity of
the punishment). These digits constituted a number which the culprit had to
multiply by itself and then by itself again, showing all the working and the
carry digits. You then had to "bring it back" - not a reference to the
effect of school dinners on your digestion, but long division twice to end
up with the number that you first thought of, again showing all the working.
Consequently some (most?) of us became very good at long multiplication and
division! I suppose as a punishment this was marginally more useful than the
prefects' punishment of getting you to fill in all the "counters" (enclosed
loops) of letters such as e or o from a page of The Times, with a standard
rate of one extra paragraph from the following day's paper for every letter
that you missed the first time round!


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