Website Caluclator

Hi there!

I need a calculator to be built so that i can insert into a php website.

The caluclator will be used by potential customers so that they can get estimates of benefits associated with our product.

The calculator should only be very simple and the calculations needed will be provided.

I have attached a drawing of how i see the calculator, however, this can be changed as it is not critical. I will welcome any advice.

The calculation is below:

Deadman x 1 =

Materials:

1 x 5ft tube
3 x doubles
1 x single

Weight:

7.2kg saving

Time:

2mins 30secs.

I hope this all makes sense, will need this doing fairly quickly.