Conditional calculating

Hello,
Is there an option of conditional calculation? For example:
I have two types of table legs:
Basic: 100€
Cross: 200€
Also calculate m2 of table plate from 50€/m2:
input field for width: in mm
dropdown with this options for height: 600, 700, 800, 900, 1000
So if i put in input 1000mm*600mm = 0,6m2 = 30€ + Basic legs 100€ = 130€
But if i choose an option 700 i want to multiply by number 1,05 or + 5%
if i choose 800 i want to multiply by number 1,10 or + 10% etc
thanks for any advice

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