Decimal Places?

tomstickland

Let's say that you use 2000 units in a year.
Total paid per year will be the unit price multiplied by the number of units.
So a 0.001 resolution on unit price will give 2p resolution in total price paid.

tomstickland

Gareth56 wrote: »

So the [greedy] energy companies charge down to the level of a thousandth of a pence because they want to do us a favour!! :eek:

Presumably then we can see energy unit prices quoted to 4 decimal places before long then.

Good smoke screen for hefty price rises though isn't it;)

Giving the unit price in ever more decimal places is not greedy or in any way a deceit. It just describes the price in more detail.

Let's say that the true asking price for baked beans in a supermarket was 89.36p.
The supermarket only charges to the nearest pound, so you pay £1 per tin and lose out.
They then decide to work to the nearest 10p, so charge 90p per tin. You still lose.
At 1p they charge 89p and you gain slightly.
At 0.1p they charge 89.4p and you lose out slightly.
At 89.36p you don't win or lose.

If you buy 100 cans though, they charge you £89.36 and you'll never know whether you gained or lost a fraction of a penny.

Gareth56

But as someone has correctly pointed out, using prices to 3 d.p. brings in an extra £10.8 million.

BexTech

Gareth56 wrote: »

But as someone has correctly pointed out, using prices to 3 d.p. brings in an extra £10.8 million.

So when prices are going up, instead of a price for example going up from 2.841 to 2.926 you'd rather it go up to 2.93 ?

Seems rather silly to me.

tomstickland

Gareth56 wrote: »

But as someone has correctly pointed out, using prices to 3 d.p. brings in an extra £10.8 million.

I don't think you really understand how numbers are rounded up or down.
If it is rounded to 2 decimal places then you can win or lose depending on whether the true value is above or below 0.005p.

Gareth56

tomstickland wrote: »

I don't think you really understand how numbers are rounded up or down.

Would you therefore care to enlighten me as to this mathematical procedure. I'd be very grateful

tomstickland

There's the true price that would have to be expressed to an infinite number of decimal places.
The advertised price is rounded to the nearest number of decimal points, as chosen by the supplier.

If the true price was increased smoothly in small amounts, the amount that you pay per year would go up in a series of steps. Looking at the flat bits between the steps then for half of it you'd be paying more than you really owed and for the other half you'd be paying less than you really owed.

BusinessEnergyBroker

If an item was £1 they could simply pocket the pound and wouldn't need to open the till for the 1p change. Similar with other prices. Very old method of ensuring staff don't steal from the till.

That leaves pound shops screwed then!!
:rotfl:

Gareth56

Originally Posted by tomstickland
I don't think you really understand how numbers are rounded up or down.


Therefore again could you show me with [possible] examples how this mathematical procedure works? That is, what are the rules of rounding up and rounding down?

I'd be very grateful

espresso

Gareth56 wrote: »

Therefore again could you show me with [possible] examples how this mathematical procedure works? That is, what are the rules of rounding up and rounding down?

See if you can get your head around this here

:rolleyes: