Reducing Balance Formula

[tcorcoran15]

Hello All,

I am trying to create a formula to look at the following:

On one tab ('Purchases') I have an amount of product pre-purchased.

	A	B
1	Amount	Balance
2	500,000	X
3	250,000	X

<tbody>
</tbody>

On another tab ('Product Sold')I have a list of all the products used as follows:

****** id="cke_pastebin" style="position: absolute; top: 192.8px; width: 1px; height: 1px; overflow: hidden; left: -1000px;">

A	B
1	Amount	Balance
2	500,000	X

<tbody>
</tbody>

</body>

	A	B
1	Reference	Amount
2	Alan	380,000
3	Tom	120,000
4	Jack	180,000

<tbody>
</tbody>

As there has been 680,000 sold, I would like the balance in the first column on 'Purchases' tab to read 0 and then in the second column, I would like it to read 70,000 as this element is still unsold.

Thanks in advance for any help.

 

[tcorcoran15]

****** id="cke_pastebin" style="position: absolute; top: 192.8px; width: 1px; height: 1px; overflow: hidden; left: -1000px;">

A	B
1	Amount	Balance
2	500,000	X

<tbody>
</tbody>

The above section should be ignored, I am unsure why it has pulled through like this.

 

[mole999]

****** id="cke_pastebin" style="position: absolute; top: 192.8px; width: 1px; height: 1px; overflow: hidden; left: -1000px;">

A	B
1	Amount	Balance
2	500,000	X

<tbody>
</tbody>

The above section should be ignored, I am unsure why it has pulled through like this.

Its related to an editor often seen with chrome