Use 1 quantity field to calculate 3 products

Hello,

I am have different product fields that have prices attached to each.
I also have a quantity field so that it can calculate the total.
Is there a way to use one quantity field to multiply the 3 products by to get a correct total.

Right now it multiplies product 1 by the quantity and adds products 2&3 instead of multiplying both of those products by the quantity as well.

Please help!

Yes I have disabled the quantity fields.

Here is my form:
http://www.foodtruckcatering.net/trucks/burgermonster/catering/request/#form

The first product is "Choose Your Package" with the prices as $5, $7.50, $7.50
The next product is "Side add-on" with the prices as $2, $2
The final product is "Drink add-on" with the prices as $1, $3, $3

The quantity is "Number of guests"

I also have a final product that is a calculation product called "Tax" with multiplies the total of the three products by 0.0775.

What i want it to do is: Total = (p1+p2+p3)*q + tax

Now i have tried a work around so that i get the total to be correct by using similar calculator for my add-ons like i did with taxes, but it the amount that the "add-on" total shows is off by the original price of the add-ons. But if i don't have that in there the total wont be correct.
What the form is doing now looks like the following:

add-on = (q*(p2 + p3))-(p2+p3)
tax = 0.0775*q*(p1+p2+p3)
Total = (q*p1) + tax + add-on

This displays like this:

add-on = short by (p2+p3)
tax = correct
total = correct

Sorry if this was long and drawn out. Hopefully this makes it clearer. If not play around with it on the link i provided.

Thanks

Hi,
I cannot find the place on the side to post a support ticket, so now I post one in a related support ticket to get the answer to my question.
I am selling personal pictures printed on canvas
Do you have an idea how to set up the following Custom product in woo commerce? (i have grativity forms add-on installed)
1) first choice is choosing the frame around the canvas (here is possibility: a, b and c)
if "c" is chosen, one of seven possibilites can be chosen (c1,c2,c3,c4,c5,c6,c7)

2) select print size:
here one possibility can be chosen (20x20cm,20,40cm up to 200x300cm)

I need a setup that shows the total price if for instances the following combination is chosen: "c," "c5", and "150x80cm" . A total price x is generated

if instead the combination possibility is chosen: "a", "180x80cm". A total price y is generated.

How can I handle this? i cannot figure out how to handle the price for the frame type (a,b,c) is dependent on the print size chosen (20x20 cm., 20x40...).

3)
I need a buttom, so customer can opload the number of pictures he/she watns in the picture. The price is x per. uploaded picture, which must be added to te total price.

I really hope you are willing to explain for me step by step, how to setup this form.

looking forward to hearing from you