Arithmetic for Idiots (Not for you!)

At age eleven I was educated, at primary school, in Cost Price, Selling Price, and the percentages in gains and losses. That training stands me in good stead today.

Here is a comprehensive and comprehensible example.

If arithmetic is not your strong point, I have laid it out, step by step:-

A jar of pills costs (say) one dollar.

Then the price goes up to six dollars.

That's an increase of five dollars.

Now one dollar is the original price.

The price is now six dollars, six hundred percent of the original price.

First Mistake

Some idiots think that means that the price has gone up by six hundred percent. But it hasn't done so.

The price has gone up by five dollars TO six dollars.

One dollar is one hundred percent.

So the price has gone up by five hundred percent TO six hundred percent.

That's the first mistake that an idiot makes.

Second Mistake

The price falls back to one dollar (Hooray!)

An idiot thinks of this as a reversal of the increase, and since they think that the increase was six hundred percent, or even five hundred percent, they think of "reversal" as a decrease of six hundred percent, or even a decrease of five hundred percent.

Hence the idiot will declare "prices have gone down by six hundred percent"

Do not take the words of such an idiot as an honest statement.

And beware of other statements from that sort of idiot.

An idiot who has not mastered primary school arithmetic must not be voted into public office.

Search