If it is given that Y and Z are correlated while X with Y and Y with Z is uncorrelated, how to find Var(X/(Y+Z))?

#1
Hi, I'm just wondering. If the variance, covariance and expected values of each variables are given. How to find the Var(X/(Y+Z)) using the delta method? Thank you in advance.
 
#3
Hi, thank you for your reply. I have tried dividing the variance into 2 parts. My working is attached below. However, by using this way, I was not able to calculate because the values of individual X, Y and Z are not given.

Working.JPG