16-year-old Helena Muffly wrote exactly 100 years ago today:
Thursday, October 26, 1911: Have such difficult algebra
problems. So much work it is to find the H.C. F. and L.C.M. Good
bye for me if we happen to get one of these in examination. Her
middle-aged granddaughter’s comments 100 years later: Important:
If you aren’t into math—skip my comments today and come back
tomorrow. Suffice it to say that Grandma was doing some fairly
difficult algebra. But, if you enjoy math here’s my take on what
this diary entry is talking about– First I’ll give an example of
the L.C.M. (lowest common multiple) and H.C.F. (highest common
factor) of two whole numbers (integers); then I’ll explain how
it’s done for algebraic expressions. The L.C.M. is the smallest
integer that two whole numbers can be divided by. 1 would always
be the L.C.M. For example, for 8 and 12 the L.C.M. would be 1.
The H.C.F.(highest common factor) is the largest integer that
two whole numbers can be divided by. For the same two numbers (8
and 12), the H