Cumulative Calculation

[agfraser76]

Hello,

I have a little problem here, I need to calculate the price o
mailboxes that we protect.

So for the fisrt 1000 mailboxes it 90 p per mailbox per month
for the next 1001-2500 mailboxes its 70 p per mailbox,
for the next 2501-5000 mailboxes its 55 p per mailbox.
etc

Now if the customer has 4700 mail boxes I need a formula that muliplie
1000 by .90 then adds to that 2500 x .70 and 1200 x .55.

So what I would like is to have one cell where you enter the number o
mailboxes and in the next cell it automatically calculates the above
and gives out the number.

It somehow needs to be able to break down the number of mailboxes i
the number of mailboxes field into the tirs above.

Just cannot get my head around it. please help.

Many Thank

 

[agfraser76]

thanks, I managed to sort it out with this formula

=MAX(MIN(0.6*$D60,600),0)+MAX(MIN(0.5*($D60-1000),750),0)+MAX(MIN(0.4*($D60-2500),1000),0)+MAX(MIN(0.25*($D60-5000),624.75),0)+MAX(MIN(0.225*($D60-7499),562.275),0