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The Bible, for example, uses fractions. In Lev. 5:16 - "He must make restitution for what he has failed to do in regard to the holy things, add a fifth of the value to that and give it all to the priest, who will make atonement for him with the ram as a guilt offering, and he will be forgiven."

But I'm with pflats' judgement. I see text like "Indeed, on computers systems which don’t have a hardware multiplication circuit, every time you write ab the computer will repeatedly add the number a for a total of b iterations." and wonder first, won't the target audience be confused by "hardware multiplication circuit", and second, is this actually true? I'm pretty sure they use shift-and-add.

Or, there's a use of "=" to say that "a/b = ... = one bth of a" then on the same page there's a triple bar "≡" used for the same thing. Will your target audience understand the notation shift?

The language "It is worth clarifying what" and "It is interesting to note that" and "We will now illustrate how the equations of kinematics are used to solve physics problems" are part of the same stultifying language you complain about. There's a bunch of places where you can simplify text like "the expression 5×32 +13 is to be interpreted" to "the expression 5×32 +13 is interpreted" -- the "to be" is useless. And the voice changes from "we get" to "you get".

Why is x<sup>-1</sup> different from f<sup>-1</sup> ? That is, the first is 1/x and the second is the function inverse. As far as I see, you don't explain that those "-1"s mean different things. Nor do you say that "f" is another type of variable naming pattern, which describes a functions.

Suppose your student wants to actually do the Moroccan example as an experiment. It will fail, because of air friction. Yet friction isn't brought up here. Newton's laws are not intuitive, because we are used to a world which is full of friction, and frictional forces aren't easy to describe. But the text assumes that the clarity of Newton's laws will be self-apparent, even if it doesn't match expectations.

The Moroccan example also uses "44.145[m]". Who measures their balcony height down to the millimeter? The precision was chosen so the answer would be exactly 3[s], but other examples aren't that fussy. In any case, the answer should be 3.00". Significant figures are hard for students to understand, and I don't see any guidance that a fall of 44 meters should not be answered 2.9950690022496134[s], even if that's what the computer gives.

Finally, good on you for using SI for the file size instead of base 210 units. However, [Mb] is megabit, not megabyte. You should use [MB].

Traditional Jewish sources would translate that as 25%. It does say one-fifth, but it's a fifth in the sense that you pay 125%, and 25% is one fifth of what you pay. There have been shifts in a lot of mathematical concepts over time and that's just one example. For instance, at some points in history people did use fractions, but favored using one in the numerator - 3/5 would have been expressed as 1/2 plus 1/10.

My goal was to find counter-examples to the phrase "The notion of 2.5 goats didn’t make any sense to the people of those days. They would have been totally confused by the menu at Rotisserie Romados which offers 1/4 of a chicken."

Sure, just nitpicking.

How about half a baby? http://en.wikipedia.org/wiki/Judgment_of_Solomon

That would have been a perfect response! I can't believe I forgot about it.

> The Bible, for example, uses fractions. In Lev. 5:16

My interest was piqued. I've asked a question at one of the Stack Exchange sites.



"The fraction one-fifth is likewise common (Lev. 5:16; 22:14)." "In ritual observances the fraction one-tenth occurs frequently (Num. 28)." "The term pi shenayim originally meant two-thirds but subsequently came to signify "twice as much" (II Kings 2:9)."

As for the translation, I used NIV. Some others will actually say 20% for that quote.

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