# Assigning Cahn-Ingold-Prelog priority numbering rules for 2 groups

I was asked to draw the perspective formula of

$$\ce{(3R,4R)CH2=CH-CH(CH3)-CH(CH3)-CH2-CH3}$$

Then I had to assign priority between the two groups:

$$\ce{-CH=CH2}$$ and $$\ce{-CH(CH3)-CH2-CH3}$$

Actually, they are bonded to the same atoms until the end of the first group, but one of them should have priority over the other. Can please someone help?