Excel question

Steve_xx

No of units 10

Cost per unit 1

Percentage discount 0.3

Total =SUM(B15*C15*(1-D15))


The above is what it looks like when I display the formula. Note that I was experimenting and not using cells a1, b1 and c1. So it's 10 units x £1 - 30% = £7

Stompa

Steve_xx wrote: »

Total =SUM(B15*C15*(1-D15))

You shouldn't have SUM, it should be just =B15*C15*(1-D15)

Steve_xx

ok I have removed "SUM", but the answer is the same, ie £7. However, I can see that the way you originally wrote it will now work in the sense that it doesn't tell me there's an error and and do I want to fix it, and it no longer requires the bracket after the = sign and at the end on the formula.

Can you say what the difference should be with and without SUM? I thought all excel formulas had the SUM thing in them.

Lokolo

SUM = to add up...

So

SUM(A1:C1) will add all the values in A1, B1 and C1.

Steve_xx

Lokolo wrote: »

SUM = to add up...

So

SUM(A1:C1) will add all the values in A1, B1 and C1.

Yes I thought that and that's what I've always done and I thought that you used the SUM formula for everything.

So, what instances do you use the = for, apart from the one I'm messing about with?

Stompa

Steve_xx wrote: »

ok I have removed "SUM", but the answer is the same, ie £7.

Can you say what the difference should be with and without SUM? I thought all excel formulas had the SUM thing in them.

No, you only use SUM when you want to add up some cells, but that's not what you're doing in this case.

In your example it'll give you the same answer, but it's completely pointless and just makes the formula more complicated than it need be.

Stompa

Steve_xx wrote: »

So, what instances do you use the = for, apart from the one I'm messing about with?

You use = in ALL formula. You use SUM only when you're adding cells.

Steve_xx

Stompa wrote: »

You use = in ALL formula. You use SUM only when you're adding cells.

Excellent. Thanks for your help with this. That's sorted me out nicely, and I've learned a bit more too.

Should I use SUM when I'm minusing, or only when adding?

Stompa

Steve_xx wrote: »

Should I use SUM when I'm minusing, or only when adding?

You should only use it when you're adding the contents of more than one cell. For example, to add several different cells you could use:

=A1+B1+C1+D1+E1+F1+G1

or:

=SUM(A1:G1)

They both do the same thing.

You shouldn't use it when you're adding or subtracting using a formula like:

=A1+D1+F2

or

=A1-D2

etc....

Steve_xx

OK I see what you mean. In my equation where the answer is £7, I understand what's happening upto this bit =B15*C15* but I don't quite grasp how this bit works (1-D15) and how you now what to write?